bluuebunny/crossref_metadata_2025 huggingface dataset:
UPSC SVPWM controlled multi‐level inverter topology for multiple pole‐pair induction motor drive for minimising torque ripple
Authors: Keerthipati Sivakumar , Nallamekala Kiran Kumar
Published: February 2016

The demand for multi‐level inverters is increasing progressively in motor control applications. Many pulse width modulation (PWM) techniques are proposed in the literature and one of the popular modulation methods is unipolar phase shifted carrier (UPSC) PWM. This PWM technique is commonly used in uninterrupted power supply applications where transformer multiple primary windings are connected to two‐level inverters. However, this modulation technique is not popularly used in drives applications because a conventional induction motor consists of only two terminals per phase. In this study, a multi‐level inverter configuration for four pole induction motor drive is presented, where it is compatible to use the above mentioned PWM technique. By using this multi‐level inverter configuration and UPSC PWM technique, all lower order harmonics are shifted to four times the switching frequency, which in turn reduces the torque ripple considerably. The proposed concept is tested on 5hp four‐pole induction motor in MATLAB/Simulink and finite element analysis and is also experimentally verified with a laboratory prototype. The simulation and experimental results show the effectiveness of the proposed topology and demonstrate the improvement in harmonic profile and torque ripple.
Morphology selective preparation and formation mechanism of graphene nanoribbons from graphite by liquid-phase pulsed laser ablation
Authors: Ren X. D. , Liu R. , Zheng L. M. , Ren Y. P. , Hu Z. Z. , He H.
Published: February 2016

The paper studied preparation and formation mechanism of free-standing 3D graphene nanoribbons (GNRs) from graphite by pulsed laser ablation in liquid. The method to fabricate freestanding graphene nanoribbons directly was simple and controllable, which does not need other precursor materials and has no byproducts. Prepared graphene nanoribbons are shown composed of up to 14 layers of graphene, spaced about 0.30–0.35 nm and have a length of hundreds of nanometers. Formation mechanism of graphene nanoribbons was proposed based on the interaction between laser and material which can be demonstrated that the exfoliation of GNRs is a carbon plasma collision connecting-graphene segments-graphene sheets-multilayer graphene-graphene nanoribbons process. The high degree of repeatability and particularity found in the obtained GNRs might suggest their unique advantages and potential applications in nano-devices and spin electronics.
Surface plasma waves with their harmonics generation from pre-structured targets
Authors: Pan K. Q. , Zheng C. Y. , He X. T.
Published: February 2016

Surface plasma waves with their harmonics are generated from pre-structured targets. The harmonics are generated by coherent synchrotron emission or relativistically oscillating mirror and then resonantly amplified by surface plasma wave excitation. Two dimensional particle-in-cell simulations and the theoretical analysis show that the laser is coupled to the structured target by generating a periodic current. Some of the generated harmonics have half integer wave numbers but integer frequencies. This interesting phenomenon is controlled by the structure period of the target.
A numerical efficient way to minimize classical density functional theory
Authors: Edelmann Markus , Roth Roland
Published: February 2016

The minimization of the functional of the grand potential within the framework of classical density functional theory in three spatial dimensions can be numerically very demanding. The Picard iteration, that is often employed, is very simple and robust but can be rather slow. While a number of different algorithms for optimization problems have been suggested, there is still great need for additional strategies. Here, we present an approach based on the limited memory Broyden algorithm that is efficient and relatively simple to implement. We demonstrate the performance of this algorithm with the minimization of an inhomogeneous bulk structure of a fluid with competing interactions. For the problems we studied, we find that the presented algorithm improves performance by roughly a factor of three.
Formation mechanisms and optimization of trap-based positron beams
Authors: Natisin M. R. , Danielson J. R. , Surko C. M.
Published: February 2016

Described here are simulations of pulsed, magnetically guided positron beams formed by ejection from Penning-Malmberg-style traps. In a previous paper [M. R. Natisin et al., Phys. Plasmas 22, 033501 (2015)], simulations were developed and used to describe the operation of an existing trap-based beam system and provided good agreement with experimental measurements. These techniques are used here to study the processes underlying beam formation in more detail and under more general conditions, therefore further optimizing system design. The focus is on low-energy beams (∼eV) with the lowest possible spread in energies (<10 meV), while maintaining microsecond pulse durations. The simulations begin with positrons trapped within a potential well and subsequently ejected by raising the bottom of the trapping well, forcing the particles over an end-gate potential barrier. Under typical conditions, the beam formation process is intrinsically dynamical, with the positron dynamics near the well lip, just before ejection, particularly crucial to setting beam quality. In addition to an investigation of the effects of beam formation on beam quality under typical conditions, two other regimes are discussed; one occurring at low positron temperatures in which significantly lower energy and temporal spreads may be obtained, and a second in cases where the positrons are ejected on time scales significantly faster than the axial bounce time, which results in the ejection process being essentially non-dynamical.
Spontaneous emergence of non-planar electron orbits during direct laser acceleration by a linearly polarized laser pulse
Authors: Arefiev A. V. , Khudik V. N. , Robinson A. P. L. , Shvets G. , Willingale L.
Published: February 2016

An electron irradiated by a linearly polarized relativistic intensity laser pulse in a cylindrical plasma channel can gain significant energy from the pulse. The laser electric and magnetic fields drive electron oscillations in a plane making it natural to expect the electron trajectory to be flat. We show that strong modulations of the relativistic γ-factor associated with the energy enhancement cause the free oscillations perpendicular to the plane of the driven motion to become unstable. As a consequence, out of plane displacements grow to become comparable to the amplitude of the driven oscillations and the electron trajectory becomes essentially three-dimensional, even if at an early stage of the acceleration it was flat. The development of the instability profoundly affects the x-ray emission, causing considerable divergence of the radiation perpendicular to the plane of the driven oscillations, while also reducing the overall emitted energy.
Parabolic temporal profiles of non-spanning avalanches and their importance for ferroic switching
Authors: He X. , Ding X. , Sun J. , Salje E. K. H.
Published: February 2016

Computer simulation of a ferroelastic switching process shows avalanche formation with universal averaged temporal avalanche profiles ⟨J(t)⟩, where J(t) is the avalanche “amplitude” at time t. The profiles are derived for the three most commonly used “jerk”-singularities, namely, the total change of the potential energy U via J(t) = (dU(t)/dt)2, the energy drop J(t) = −dU/dt, and the stress drop J(t) = −dτxy/dt. The avalanches follow, within the time resolution of our modeling, a universal profile J(t)/Jmax = 1 − 4(t/tmax − 0.5)2 in the a-thermal regime and the thermal regime. Broadening of the profiles towards a 4th order parabola arises from peak overlap or peak splitting. All profiles are symmetric around t/tmax = 0.5 and are expected to hold for switching processes in ferroic materials when the correlations during the avalanche are elastic in origin. High frequency applications of ferroic switching are constrained by this avalanche noise and its characteristic temporal distribution function will determine the bandwidth of any stored or transmitted signal.
Resolving fine spectral features in lattice vibrational modes using femtosecond coherent spectroscopy
Authors: Card A. , Mokim M. , Ganikhanov F.
Published: February 2016

We show resolution of fine spectral features within several Raman active vibrational modes in potassium titanyl phosphate (KTP) crystal. Measurements are performed using a femtosecond time-domain coherent anti-Stokes Raman scattering spectroscopy technique that is capable of delivering equivalent spectral resolution of 0.1 cm−1. The Raman spectra retrieved from our measurements show several spectral components corresponding to vibrations of different symmetry with distinctly different damping rates. In particular, linewidths for unassigned optical phonon mode triplet centered at around 820 cm−1 are found to be 7.5 ± 0.2 cm−1, 9.1 ± 0.3 cm−1, and 11.2 ± 0.3 cm−1. Results of our experiments will ultimately help to design an all-solid-state source for sub-optical-wavelength waveform generation that is based on stimulated Raman scattering.
Multiple cameras required to reliably detect feral cats in northern Australian tropical savanna: an evaluation of sampling design when using camera traps
Authors: Stokeld Danielle , Frank Anke S. K. , Hill Brydie , Choy Jenni Low , Mahney Terry , Stevens Alys , Young Stuart , Rangers Djelk , Rangers Warddeken , Gillespie Graeme R.
Published: February 2016

Context Feral cats are a major cause of mammal declines and extinctions in Australia. However, cats are elusive and obtaining reliable ecological data is challenging. Although camera traps are increasingly being used to study feral cats, their successful use in northern Australia has been limited. Aims We evaluated the efficacy of camera-trap sampling designs for detecting cats in the tropical savanna of northern Australia. We aimed to develop a camera-trapping method that would yield detection probabilities adequate for precise occupancy estimates. Methods First, we assessed the influence of two micro-habitat placements and three lure types on camera-trap detection rates of feral cats. Second, using multiple camera traps at each site, we examined the relationship between sampling effort and detection probability by using a multi-method occupancy model. Key results We found no significant difference in detection rates of feral cats using a variety of lures and micro-habitat placement. The mean probability of detecting a cat on one camera during one week of sampling was very low (p = 0.15) and had high uncertainty. However, the probability of detecting a cat on at least one of five cameras deployed concurrently on a site was 48% higher (p = 0.22) and had a greater precision. Conclusions The sampling effort required to achieve detection rates adequate to infer occupancy of feral cats by camera trap is considerably higher in northern Australia than has been observed elsewhere in Australia. Adequate detection of feral cats in the tropical savanna of northern Australia will necessitate inclusion of more camera traps and a longer survey duration. Implications Sampling designs using camera traps need to be rigorously trialled and assessed to optimise detection of the target species for different Australian biomes. A standard approach is suggested for detecting feral cats in northern Australian savannas.
Host immunity shapes the impact of climate changes on the dynamics of parasite infections
Authors: Mignatti Andrea , Boag Brian , Cattadori Isabella M.
Published: February 2016

Significance

To understand and mitigate the impact of climate change on host-parasite trophic interactions, we need to know how variation in immune responses among hosts can modify the effect of warming on infectious disease processes. By modeling the dynamics of infection of two parasite species in a rabbit population, we show that immunity can interact with climate. Specifically, the annual intensity of infection remains relatively constant over time, although younger hosts carry heavier infections in the summer in warming years. In contrast, in the second parasite the lack of immune control leads the intensity to increase with warming. Immunity can reduce the severity of population infection, but it can also exacerbate parasite intensity in the younger individuals exposed to climate warming.
Probing the promiscuity of
ent
-kaurene oxidases via combinatorial biosynthesis
Authors: Mafu Sibongile , Jia Meirong , Zi Jiachen , Morrone Dana , Wu Yisheng , Xu Meimei , Hillwig Matthew L. , Peters Reuben J.
Published: February 2016

Significance

Combinatorial biosynthesis is enabled by the use of promiscuous enzymes, but also can be applied to the discovery of such biocatalysts. Here, such an approach was used for the investigation of the substrate selectivity of cytochrome P450 enzymes from diterpenoid phytohormone biosynthesis, enabling facile characterization of both multiple substrates and structural analysis of the resulting products. The discovery of one such promiscuous cytochrome P450, reported here, provides insight into the underlying structure–function relationship and also may have biotechnological implications.
Widespread collapse of the Ross Ice Shelf during the late Holocene
Authors: Yokoyama Yusuke , Anderson John B. , Yamane Masako , Simkins Lauren M. , Miyairi Yosuke , Yamazaki Takahiro , Koizumi Mamito , Suga Hisami , Kusahara Kazuya , Prothro Lindsay , Hasumi Hiroyasu , Southon John R. , Ohkouchi Naohiko
Published: February 2016

Significance

The Ross Sea is a major drainage basin for the Antarctic Ice Sheet and contains the world’s largest ice shelf. Newly acquired swath bathymetry data and sediment cores provide evidence for two episodes of ice-shelf collapse. Two novel geochemical proxies, compound specific radiocarbon dating and radiogenic beryllium (
10
Be), constrain the timing of the most recent and widespread (∼280,000 km
2
) breakup as having occurred in the late Holocene. Three-dimensional ice-shelf/ocean modeling results and comparison with ice-core records indicate that oceanic and atmospheric warming caused ice-shelf collapse.
Cognitive fatigue influences students’ performance on standardized tests
Authors: Sievertsen Hans Henrik , Gino Francesca , Piovesan Marco
Published: February 2016

Significance

We identify one potential source of bias that influences children’s performance on standardized tests and that is predictable based on psychological theory: the time at which students take the test. Using test data for all children attending Danish public schools between school years 2009/10 and 2012/13, we find that, for every hour later in the day, test scores decrease by 0.9% of an SD. In addition, a 20- to 30-minute break improves average test scores. Time of day affects students’ test performance because, over the course of a regular day, students’ mental resources get taxed. Thus, as the day wears on, students become increasingly fatigued and consequently more likely to underperform on a standardized test.
First structure of full-length mammalian phenylalanine hydroxylase reveals the architecture of an autoinhibited tetramer
Authors: Arturo Emilia C. , Gupta Kushol , Héroux Annie , Stith Linda , Cross Penelope J. , Parker Emily J. , Loll Patrick J. , Jaffe Eileen K.
Published: February 2016

Significance

Phenylketonuria and milder hyperphenylalaninemias constitute the most common inborn error of amino acid metabolism, usually caused by defective phenylalanine hydroxylase (PAH). Although a highly restricted diet prevents intellectual impairment during development, additional therapies are required to combat cognitive dysfunction, executive dysfunction, and psychiatric disorders that arise due to dietary lapses throughout life. New therapies can arise from thorough understanding of the conformational space available to full-length PAH, which has defied crystal structure determination for decades. We present the first X-ray crystal structure of full-length PAH, whose solution relevance is supported by small-angle X-ray scattering. The current structure is an autoinhibited tetramer; the scattering data support the existence of an architecturally distinct tetramer that is stabilized by the allosteric activator phenylalanine.
Cholesteryl esters stabilize human CD1c conformations for recognition by self-reactive T cells
Authors: Mansour Salah , Tocheva Anna S. , Cave-Ayland Chris , Machelett Moritz M. , Sander Barbara , Lissin Nikolai M. , Molloy Peter E. , Baird Mark S. , Stübs Gunthard , Schröder Nicolas W. J. , Schumann Ralf R. , Rademann Jörg , Postle Anthony D. , Jakobsen Bent K. , Marshall Ben G. , Gosain Rajendra , Elkington Paul T. , Elliott Tim , Skylaris Chris-Kriton , Essex Jonathan W. , Tews Ivo , Gadola Stephan D.
Published: February 2016

Significance

T cells autoreactive to cluster of differentiation 1c (CD1c) are abundant in human blood but lipid antigens recognized by these T cells remained poorly understood. A new 2.4-Å structure of CD1c and computational simulations thereof indicated substantial conformational plasticity of CD1c with ligand-induced formation of an F′ roof and G′ portal, as well as the potential of CD1c to present acylated sterols. Confirming these predictions we demonstrated CD1c loading and biophysical interaction of CD1c–lipid complexes with self-reactive human T-cell receptors for two lipid classes: cholesteryl esters similar to those accumulating in foamy macrophages (e.g., in atherosclerosis) and acylated steryl glycosides fromBorrelia burgdorferi. These findings differentiate CD1c from other CD1 isoforms and open up new avenues for research into the role of CD1c in human immunity.
Load-dependent destabilization of the γ-rotor shaft in F
O
F
1
ATP synthase revealed by hydrogen/deuterium-exchange mass spectrometry
Authors: Vahidi Siavash , Bi Yumin , Dunn Stanley D. , Konermann Lars
Published: February 2016

Significance

F
O
F
1
, or ATP synthase, is often referred to as the “world’s smallest motor.” Similar to automotive engines, it employs a rotating shaft that interacts with mechanical actuators. When operating a combustion engine under load, the bearings exert significant forces on the crankshaft, leading to enhanced mechanical stress. Here, we demonstrate that analogous load-dependent effects occur in molecular motors. When F
O
F
1
pumps protons against a transmembrane gradient, the rotor shaft undergoes structural destabilization attributed to resistive forces in its apical bearing. The effect disappears when the transmembrane gradient opposing proton pumping is short-circuited by an uncoupler, as predicted by fundamental principles of mechanics. Our observations highlight fascinating parallels between engine operation on the macroscale and the nanoscale.
Crossover from metal to insulator in dense lithium-rich compound CLi
4
Authors: Jin Xilian , Chen Xiao-Jia , Cui Tian , Mao Ho-kwang , Zhang Huadi , Zhuang Quan , Bao Kuo , Zhou Dawei , Liu Bingbing , Zhou Qiang , He Zhi
Published: February 2016

Significance

The binary compound researched here enriches the studies of antimetallization just like in the pure elemental system, and the fundamental nature of matter in the subject has been expanded. During metallizing or antimetallizing in metallic states, the Fermi surface filling parameter is found to be a valuable parameter to quantify the evolution of the free electrons.
New tools for studying microglia in the mouse and human CNS
Authors: Bennett Mariko L. , Bennett F. Chris , Liddelow Shane A. , Ajami Bahareh , Zamanian Jennifer L. , Fernhoff Nathaniel B. , Mulinyawe Sara B. , Bohlen Christopher J. , Adil Aykezar , Tucker Andrew , Weissman Irving L. , Chang Edward F. , Li Gordon , Grant Gerald A. , Hayden Gephart Melanie G. , Barres Ben A.
Published: February 2016

Significance

Microglia are the tissue resident macrophages of the brain and spinal cord, implicated in important developmental, homeostatic, and disease processes, although our understanding of their roles is complicated by an inability to distinguish microglia from related cell types. Although they share many features with other macrophages, microglia have distinct developmental origins and functions. Here we validate a stable and robustly expressed microglial marker for both mouse and human, transmembrane protein 119 (Tmem119). We use custom-made antibodies against Tmem119 to perform deep RNA sequencing of developing microglia, and demonstrate that microglia mature by the second postnatal week in mice. The antibodies, cell isolation methods, and RNAseq profiles presented here will greatly facilitate our understanding of microglial function in health and disease.
Differential regulation of type III secretion and virulence genes inBordetella pertussisandBordetella bronchisepticaby a secreted anti-σ factor
Authors: Ahuja Umesh , Shokeen Bhumika , Cheng Ning , Cho Yeonjoo , Blum Charles , Coppola Giovanni , Miller Jeff F.
Published: February 2016

Significance

Bordetella bronchisepticaisolates from diverse hosts, including humans, display potent cytotoxicity against a broad range of mammalian cells, which is dependent on type III secretion system (T3SS) effector BteA. In contrast, neither laboratory nor clinical isolates ofBordetella pertussishave been observed to display T3SS-dependent cytotoxicity, despite the fact that T3SS genes are present, intact, and nearly identical to theirB. bronchisepticacounterparts. We have characterized a regulatory node, involving a T3SS-exported anti-σ factor, BtrA, that controls virulence gene expression inBordetella species. Of particular relevance to human disease, deletion ofbtrAinB. pertussisderepresses T3SS gene expression and confers readily detectable BteA-dependent cytotoxicity. These observations warrant a reassessment of type III secretion in the pathogenesis and prevention of pertussis.
Arabidopsis
type B cytokinin response regulators ARR1, ARR10, and ARR12 negatively regulate plant responses to drought
Authors: Nguyen Kien Huu , Ha Chien Van , Nishiyama Rie , Watanabe Yasuko , Leyva-González Marco Antonio , Fujita Yasunari , Tran Uven Thi , Li Weiqiang , Tanaka Maho , Seki Motoaki , Schaller G. Eric , Herrera-Estrella Luis , Tran Lam-Son Phan
Published: February 2016

Significance

Cytokinin regulates plant drought adaptation via a multistep component system consisting of histidine kinases, histidine phosphotransfer proteins, and type A and B response regulators (RRs). The functional dissection of individual members of cytokinin signaling and identification of their downstream targets in drought responses are of high importance to provide a complete picture of how cytokinin controls plant drought adaptation. Previous studies have identified functions of several histidine kinases, histidine phosphotransfer proteins, and type A RRs in drought responses of
Arabidopsis
; however, the roles of type B RRs remain elusive. This comprehensive functional analysis of three type B RRs provides further insight into how cytokinin signaling regulates plant drought adaptation through the proposed yin-yang strategy, enabling efficient application of cytokinin biology in stress tolerance-oriented plant biotechnology.
MEKK2 mediates an alternative β-catenin pathway that promotes bone formation
Authors: Greenblatt Matthew Blake , Shin Dong Yeon , Oh Hwanhee , Lee Ki-Young , Zhai Bo , Gygi Steven P. , Lotinun Sutada , Baron Roland , Liu Dou , Su Bing , Glimcher Laurie H. , Shim Jae-Hyuck
Published: February 2016

Significance

Here, we report a previously unidentified alternative pathway mediated by mitogen-activated protein kinase kinase kinase 2 (MEKK2) for the activation of β-catenin in osteoblasts that is distinct from the classical glycogen synthase kinase 3β (GSK3β)-mediated degradation pathway. The GSK3β pathway regulates β-catenin stability via β-catenin ubiquitination, and its inhibition prevents β-catenin degradation. The MEKK2 pathway instead rescues ubiquitinated β-catenin from degradation via deubiquitination. This pathway plays a critical role in controlling bone mass in vivo, and targeting this pathway may offer an attractive approach for the therapeutic regulation of β-catenin activity.
Exponential stability of matrix-valued Markov chains via nonignorable periodic data
Authors: Dai Xiongping , Huang Tingwen , Huang Yu
Published: February 2016

Let

ξ
=
{

ξ
n

}

n
≥
0

\boldsymbol {\xi }=\{\xi _n\}_{n\ge 0}

be a Markov chain defined on a probability space

(
Ω
,

F

,

P

)

(\Omega ,\mathscr {F},\mathbb {P})

valued in a discrete topological space

S
\boldsymbol {S}

that consists of a finite number of real

d
×
d

d\times d

matrices. As usual,

ξ
\boldsymbol {\xi }

is called uniformly exponentially stable if there exist two constants

C
>
0

C>0

and

0
>
λ
>
1

0>\lambda >1

such that
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartLayout 1st Row double-struck upper P left-parenthesis double-vertical-bar xi 0 left-parenthesis omega right-parenthesis midline-horizontal-ellipsis xi Subscript n minus 1 Baseline left-parenthesis omega right-parenthesis double-vertical-bar less-than-or-equal-to upper C lamda Superscript n Baseline for-all n greater-than-or-equal-to 1 right-parenthesis equals 1 semicolon EndLayout">

P

(
‖

ξ
0

(
ω
)
⋯

ξ

n
−
1

(
ω
)
‖
≤
C

λ

n

 
∀
n
≥
1
)

=
1
;

\begin{gather*} \mathbb {P}\left (\|\xi _0(\omega )\dotsm \xi _{n-1}(\omega )\|\le C\lambda ^{n}\ \forall n\ge 1\right )=1; \end{gather*}

and

ξ
\boldsymbol {\xi }

is called nonuniformly exponentially stable if there exist two random variables

C
(
ω
)
>
0

C(\omega )>0

and

0
>
λ
(
ω
)
>
1

0>\lambda (\omega )>1

such that
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartLayout 1st Row double-struck upper P left-parenthesis double-vertical-bar xi 0 left-parenthesis omega right-parenthesis midline-horizontal-ellipsis xi Subscript n minus 1 Baseline left-parenthesis omega right-parenthesis double-vertical-bar less-than-or-equal-to upper C left-parenthesis omega right-parenthesis lamda left-parenthesis omega right-parenthesis Superscript n Baseline for-all n greater-than-or-equal-to 1 right-parenthesis equals 1 period EndLayout">

P

(
‖

ξ
0

(
ω
)
⋯

ξ

n
−
1

(
ω
)
‖
≤
C
(
ω
)
λ
(
ω

)

n

 
∀
n
≥
1
)

=
1.

\begin{gather*} \mathbb {P}\left (\|\xi _0(\omega )\dotsm \xi _{n-1}(\omega )\|\le C(\omega )\lambda (\omega )^{n}\ \forall n\ge 1\right )=1. \end{gather*}

In this paper, we characterize the exponential stabilities of

ξ
\boldsymbol {\xi }

via its nonignorable periodic data whenever

ξ
\boldsymbol {\xi }

has a constant transition binary matrix. As an application, we construct a Lipschitz continuous

S
L

(
2
,

R

)

\mathrm {SL}(2,\mathbb {R})

-cocycle driven by a Markov chain with

2
2

-points state space, which is nonuniformly but not uniformly hyperbolic and which has constant Oseledeč splitting with respect to a canonical Markov measure.
Viscoelastic Properties of Gelatinized Dispersions of Maize Starch Modified by Solid‐State Milling
Authors: Kochkina Nataliya , Khokhlova Yuliya
Published: February 2016

Solid‐state milling is an effective physical modification method applied to improve functional properties of starch. In this work the effect of solid‐state milling on the viscoelastic characteristics of maize starch gelatinized dispersions (gels) was investigated by using oscillatory squeeze film rheometry. The relaxation spectrum of the samples under study was calculated from the data obtained. It was found that solid‐state milling resulted in a decrease of the storage (G′) and loss (G″) moduli; meanwhile, loss tangent (tan δ) increased. At a starch milling time more than 10 h, G″ > G′ and the gelatinized starch dispersions behaved as liquid‐like systems. The relaxation maxima shifted to shorter relaxation times, and the heights of the maxima decreased with increasing milling time. The relationship between the complex viscosity η* and steady‐shear viscosity η gradually altered from η* > η to η* < η as the milling time increased. The results can be used to determine the processing conditions of milled starch.
A New Rust Disease on Wild Coffee (Psychotria nervosa) Caused by Puccinia mysuruensis sp. nov.
Authors: Mahadevakumar S. , Szabo Les J. , Eilam T. , Anikster Y. , Janardhana G. R.
Published: February 2016

Psychotria nervosa, commonly called “wild coffee” (Rubiaceae), is an important ethno-medicinal plant in India. In 2010, a new rust disease of P. nervosa was observed in three regions of Mysore District, Karnataka (India), with disease incidence ranging from 58 to 63%.Typical symptoms of the rust disease on wild coffee were prominently visible during the early monsoon season (May to June), with chlorotic spots on the adaxial and black pustules (telia) on the abaxial leaf surface. Telia produced abundant teliospores, which were bicelled, pedicillate, and measured 33 to 45 by 19 to 30 μm. The germination of teliospores produced a typical metabasidium bearing four basidiospores, each containing two haploid nuclei. Spore stages of the wild coffee rust pathogen were studied using artificially inoculated healthy wild coffee plants with germinated teliospores. Only telia were observed on the inoculated plants, indicating that this rust fungus has an abbreviated microcyclic life cycle that includes only teliospores and basidiospores. Phylogenetic analysis based on internal transcribed spacer and partial large subunit (LSU) sequence data showed that the wild coffee rust pathogen is related to Macruropyxis fraxini, Puccinia bartholomaei, P. choridis, and P. sparganioidis. The herbarium sample of P. psychotriae was examined and was shown to be different with respect to telium size and teliospore dimensions (24 to 32 by 13 to 18 μm). Therefore, the rust pathogen causing wild coffee rust is a new species, P. mysuruensis sp. nov.
Persistence of Dothistroma septosporum on Abscised Pine Needles and its Implications for Disease Management
Authors: Mullett Martin , Peace Andy , Brown Anna
Published: February 2016

Dothistroma septosporum is a serious foliar pathogen of pines in Britain. To determine the contribution of spores produced on abscised needles to the D. septosporum inoculum load in a forest environment, survival of the fungus was investigated in commercially grown plantations of Corsican pine (Pinus nigra subsp. laricio) in southern England. The fungus persisted for longer in abscised needles retained in the canopy compared with needles on the litter layer of the forest floor. High relative humidity had a significant negative effect on persistence in the canopy needles, highlighting the effect of moisture on rates of microbial decay. The median lethal time 50 (LT50) of infective propagules from needles in the litter layer was 20 to 28 days, whereas for needles suspended in the canopy it was 34 to 48 days. Microsatellite markers revealed that the population of D. septosporum deemed persistent (i.e., recovered from abscised needles after exposure for 28 to 32 weeks) was similar to the general population of D. septosporum in the forest stand (i.e., isolates recovered from attached needles and after exposure for only 4 weeks). Overall, abscised needles with acervuli of D. septosporum contribute only moderately and for a limited time to inoculum levels of the pathogen in an infected forest stand.
Serial measurement of type-specific human papillomavirus load enables classification of cervical intraepithelial neoplasia lesions according to occurring human papillomavirus-induced pathway
Authors: Verhelst Stefanie , Poppe Willy A.J. , Bogers Johannes J. , Depuydt Christophe E.
Published: February 2016

This retrospective study examined whether human papillomavirus (HPV) type-specific viral load changes measured in two or three serial cervical smears are predictive for the natural evolution of HPV infections and correlate with histological grades of cervical intraepithelial neoplasia (CIN), allowing triage of HPV-positive women. A cervical histology database was used to select consecutive women with biopsy-proven CIN in 2012 who had at least two liquid-based cytology samples before the diagnosis of CIN. Before performing cytology, 18 different quantitative PCRs allowed HPV type-specific viral load measurement. Changes in HPV-specific load between measurements were assessed by linear regression, with calculation of coefficient of determination (R
2) and slope. All infections could be classified into one of five categories: (i) clonal progressing process (R
2≥0.85; positive slope), (ii) simultaneously occurring clonal progressive and transient infection, (iii) clonal regressing process (R
2≥0.85; negative slope), (iv) serial transient infection with latency [R
2<0.85; slopes (two points) between 0.0010 and −0.0010 HPV copies/cell/day], and (v) transient productive infection (R
2<0.85; slope: ±0.0099 HPV copies/cell/day). Three hundred and seven women with CIN were included; 124 had single-type infections and 183 had multiple HPV types. Only with three consecutive measurements could a clonal process be identified in all CIN3 cases. We could clearly demonstrate clonal regressing lesions with a persistent linear decrease in viral load (R
2≥0.85; −0.003 HPV copies/cell/day) in all CIN categories. Type-specific viral load increase/decrease in three consecutive measurements enabled classification of CIN lesions in clonal HPV-driven transformation (progression/regression) and nonclonal virion-productive (serial transient/transient) processes.
Transapical Mitral Valve-in-Valve Implantation Using an Edwards SAPIEN 3 Prosthesis
Authors: Cocchieri Riccardo , Koh Ezra Y. , De Mol Bas A.
Published: February 2016

We report a case of transapical mitral valve-in-valve implantation for a deteriorated bioprosthesis using the SAPIEN 3. Our patient, a 79-year-old man, with a history of mitral valve replacement 10 years before, presented with acute dyspnea due to mitral valve dysfunction. He was successfully treated with transapical implantation and had an uneventful recovery. Our case demonstrates the feasibility of using SAPIEN 3 in treating degenerated bioprosthetic mitral valves.
First-in-Man Transcervical Surgical Aortic Valve Replacement Using the CoreVista System
Authors: Dapunt Otto E. , Luha Olev , Ebner Adrian , Sonecki Piotr , Spadaccio Cristiano , Sutherland Fraser W. H.
Published: February 2016

Objective

This study aimed to evaluate a novel device system for surgical aortic valve replacement (SAVR) using a unique new less invasive access approach. The hypothesis is that SAVR can be performed through a short transverse incision in the neck, similar to that used for transcervical thymectomy avoiding chest disruption.

Methods

A new device system was developed to provide retraction, step-by-step illumination, and on-screen visualization for the new approach. Preliminary feasibility studies were performed in cadavers. Comprehensive risk analysis was performed, and training was implemented in Thiel preserved cadavers. For the first-in-man clinical case, a 63-year-old woman with symptomatic critical aortic stenosis (The Society of Thoracic Surgeons risk, 11%) and heavily calcified aortic valve was selected. A short transverse incision was made in the neck; the device was introduced, and the sternum was elevated; femorofemoral cardiopulmonary bypass was established; substernal dissection was guided by the sequenced illumination, and highdefinition visualization was provided by the device, allowing for optimal exposition of the aorta and aortic valve; and a 23-mm Medtronic ENABLE sutureless valve prosthesis was implanted. Procedure success was evaluated according to the standardized composite end point definition of “device success” proposed by the Valve Academic Research Consortium.

Results

Access, delivery, and deployment of the valve prosthesis were successful. The correct position and intended performance of the valve were demonstrated (mean gradient, 6 mm Hg; aortic valve area, 2.5 cm2) with the absence of moderate or severe prosthetic aortic regurgitation. Only one valve prosthesis was used.

Conclusions

Transcervical SAVR with sutureless valve is feasible using this novel access system. The new approach has potential to offer patients substantially shorter stay and fewer, less serious complications, as has been observed in transcervical thymectomy. Further studies are merited.
A Simple Porcine Model of Inducible Sustained Atrial Fibrillation
Authors: Lee Anson M. , Miller Jacob R. , Voeller Rochus K. , Zierer Andreas , Lall Shelly C. , Schuessler Richard B. , Damiano Ralph J. , Melby Spencer J.
Published: February 2016

The surgical management of atrial fibrillation (AF) is an evolving field with a history of testing various lesion sets and ablation technologies. Previous animal models of AF require a chronic intervention to make AF reliably inducible. Our objective was to create an acute, reliable, and reproducible porcine model of sustained AF. To accomplish this, 21 adult domestic pigs underwent median sternotomy. Methods to induce AF were then performed sequentially: manual stimulation, rapid pacing (200 beats per minute), and then rapid pacing of 8 beats with a cycle length of 300 milliseconds, followed by an extra stimulus at decreasing cycle lengths. If AF was not induced, burst pacing was performed at a cycle length of 90 milliseconds for 30 seconds. If AF was still not induced, intravenous neostigmine was administered, and the process was repeated. Atrial fibrillation was considered sustained after 1 minute. Attempts at AF induction were successful in 18 (86%) of 21. Atrial fibrillation was induced during manual stimulation in four (19%), during rapid pacing in five (24%), during burst pacing in five (24%), and after the administration of neostigmine in four (19%). Mean (SD) duration of AF was 3.6 (2.6) minutes. Of the 18, 14 (78%) reverted to sinus rhythm spontaneously and 4 (22%) required an antiarrhythmic. This technique of inducing AF can easily be used to evaluate new technologies and lesion sets without the need for creating a chronic animal model.
Single-Incision Video-Assisted Thoracic Surgery for an Extralobar Sequestration in a Child
Authors: Halezeroğlu Semih , Okur Erdal , Ergene Gökhan
Published: February 2016

Uniportal or single-incision video-assisted thoracic surgery (VATS) has been performed successfully in adult patients with different intrathoracic pathologies for years. However, no report in uniportal/single-incision VATS in pediatric patients in the English literature has been published up to date. This may be explained by the limited number of patients and the difficulties in working in very narrow thoracic cavity of babies and children. For these reasons, all the published cases of VATS for extralobar sequestration in infants or children were performed through the three-port approach. We report herein a case of single-incision VATS in a child for the resection of an extralobar sequestration.
Outpatient treatment of uncomplicated diverticulitis: a systematic review
Authors: Sánchez-Velázquez Patricia , Grande Luis , Pera Miguel
Published: February 2016

Acute diverticulitis occurs in up to 25% of patients with diverticulosis. The majority of cases are mild or uncomplicated and it has become a frequent reason for consultation in the emergency department. On the basis of the National Inpatient Sample database from the USA, 86% of patients admitted with diverticulitis were treated with medical therapy. However, several recent studies have shown that outpatient treatment with antibiotics is safe and effective. The aim of this systematic review is to update the evidence published in the outpatient treatment of uncomplicated acute diverticulitis. We performed a systematic review according to the PRISMA guidelines and searched in MEDLINE and Cochrane databases all English-language articles on the management of acute diverticulitis using the following search terms: ‘diverticulitis’, ‘outpatient’, and ‘uncomplicated’. Data were extracted independently by two investigators. A total of 11 articles for full review were yielded: one randomized controlled trial, eight prospective cohort studies, and two retrospective cohort studies. Treatment successful rate on an outpatient basis, which means that no further complications were reported, ranged from 91.5 to 100%. Fewer than 8% of patients were readmitted in the hospital. Intolerance to oral intake and lack of family or social support are common exclusion criteria used for this approach, whereas severe comorbidities are not definitive exclusion criteria in all the studies. Ambulatory treatment of uncomplicated acute diverticulitis is safe, effective, and economically efficient when applying an appropriate selection in most reviewed studies.
Ultrasound and Electromyography Guidance for Injection of the Longus Colli With Botulinum Toxin for the Treatment of Cervical Dystonia
Authors: Allison Stephen K. , Odderson Ib R.
Published: February 2016

Cervical dystonia, also called spasmodic torticollis, is a painful condition in which neck muscles contract involuntarily, and may cause abnormal head position or movements. The primary (or first line of) treatment of cervical dystonia is chemodenervation with injection of botulinum toxin into the affected muscles. We report a case of a young man with idiopathic cervical dystonia who developed anterocollis (forward flexion of the neck) not responsive to prior scalene and sternocleidomastoid muscle injections. To safely access the deeper cervical musculature, ultrasound (US) was used in conjunction with electromyography, to inject the longus colli muscles bilaterally. The patient responded well and had no complications. The longus colli has been reported to be injected using electromyography, fluoroscopy, computed tomography, and, less frequently, US. We propose that US guidance is an excellent technique for botulinum toxin injection, especially for deep cervical muscles such as the longus colli.
Effects of Electroconvulsive Therapy on Some Inflammatory Factors in Patients With Treatment-Resistant Schizophrenia
Authors: Kartalci Sukru , Karabulut Aysun Bay , Erbay Lale Gonenir , Acar Ceren
Published: February 2016

Objectives

Electroconvulsive therapy (ECT) is the most effective option for several psychiatric conditions, including treatment-resistant schizophrenia. However, little is known about the molecular mechanism of action of ECT. The link between inflammatory system and schizophrenia is the focus of recent studies. However, the impact of ECT on inflammatory functioning in this disorder remains elusive. Whether ECT could modulate inflammatory factors in patients with schizophrenia was examined.

Methods

Plasma levels of interleukin-4 (IL-4), transforming growth factor-β (TGF-β), myeloperoxidase (MPO), and nuclear factor-κB (NF-κB) activation were analyzed in 20 schizophrenic patients, mainly with resistant to antipsychotic medication disorders, and in 20 sex- and age-matched healthy controls. Disease severity was evaluated using the Brief Psychiatric Rating Scale. All patients were followed with measurement of the inflammatory factors before and after ECT treatment and compared with the controls.

Results

Patients with schizophrenia had markedly raised NF-κB and but decreased TGF-β levels compared with healthy controls. On the other hand, no significant differences were found for the levels of IL-4 and MPO levels. The clinical improvement during repeated ECT was accompanied by a gradual and significant increase in IL-4 and TGF-β level, but MPO and NF-κB activation were left unaffected. Increases in TGF-β were negatively correlated with the change in Brief Psychiatric Rating Scale scores after ECT.

Conclusions

It is shown that ECT, while increasing the anti-inflammatory response such as the levels of IL-4 and TGF-β, it did not affect the levels of MPO and NF-κB activation in this study.
Light at night, clocks and health: from humans to wild organisms
Authors: Dominoni Davide M. , Borniger Jeremy C. , Nelson Randy J.
Published: February 2016

The increasing use of electric lights has modified the natural light environment dramatically, posing novel challenges to both humans and wildlife. Indeed, several biomedical studies have linked artificial light at night to the disruption of circadian rhythms, with important consequences for human health, such as the increasing occurrence of metabolic syndromes, cancer and reduced immunity. In wild animals, light pollution is associated with changes in circadian behaviour, reproduction and predator–prey interactions, but we know little about the underlying physiological mechanisms and whether wild species suffer the same health problems as humans. In order to fill this gap, we advocate the need for integrating ecological studies in the field, with chronobiological approaches to identify and characterize pathways that may link temporal disruption caused by light at night and potential health and fitness consequences.
Improving accuracy through density correction in guided wave tomography
Authors: Huthwaite P.
Published: February 2016

The accurate quantification of wall loss caused by corrosion is critical to the reliable life estimation of pipes and pressure vessels. Traditional thickness gauging by scanning a probe is slow and requires access to all points on the surface; this is impractical in many cases as corrosion often occurs where access is restricted, such as beneath supports where water collects. Guided wave tomography presents a solution to this; by transmitting guided waves through the region of interest and exploiting their dispersive nature, it is possible to build up a map of thickness. While the best results have been seen when using the fundamental modes A0 and S0 at low frequency, the complex scattering of the waves causes errors within the reconstruction. It is demonstrated that these lead to an underestimate in wall loss for A0 but an overestimate for S0. Further analysis showed that this error was related to density variation, which was proportional to thickness. It was demonstrated how this could be corrected for in the reconstructions, in many cases resulting in the near-elimination of the error across a range of defects, and greatly improving the accuracy of life estimates from guided wave tomography.
Oxygen-induced social behaviours inPristionchus pacificushave a distinct evolutionary history and genetic regulation fromCaenorhabditis elegans
Authors: Moreno Eduardo , McGaughran Angela , Rödelsperger Christian , Zimmer Manuel , Sommer Ralf J.
Published: February 2016

Wild isolates of the nematodeCaenorhabditis elegansperform social behaviours, namely clumping and bordering, to avoid hyperoxia under laboratory conditions. In contrast, the laboratory reference strain N2 has acquired a solitary behaviour in the laboratory, related to a gain-of-function variant in the neuropeptide Y-like receptor NPR-1. Here, we study the evolution and natural variation of clumping and bordering behaviours inPristionchus pacificusnematodes in a natural context, using strains collected from 22 to 2400 metres above sea level on La Réunion Island. Through the analysis of 106 wild isolates, we show that the majority of strains display a solitary behaviour similar toC. elegansN2, whereas social behaviours are predominantly seen in strains that inhabit high-altitude locations. We show experimentally thatP. pacificussocial strains perform clumping and bordering to avoid hyperoxic conditions in the laboratory, suggesting that social strains may have adapted to or evolved a preference for the lower relative oxygen levels available at high altitude in nature. In contrast toC. elegans, clumping and bordering inP. pacificusdo not correlate with locomotive behaviours in response to changes in oxygen conditions. Furthermore, QTL analysis indicates clumping and bordering to represent complex quantitative traits. Thus, clumping and bordering behaviours represent an example of phenotypic convergence with a different evolutionary history and distinct genetic control in both nematode species.