bluuebunny/crossref_metadata_2025 huggingface dataset:
Multichannel tunable filter properties of 1D magnetized ternary plasma photonic crystal in the presence of evanescent wave
Authors: Awasthi Suneet Kumar , Panda Ranjita , Shiveshwari Laxmi
Published: July 2017

The multichannel tunable filter properties of one-dimensional ternary plasma photonic crystal composed of magnetized plasma and lossless dielectric have been theoretically investigated using transfer matrix method in the microwave region. The proposed filters possess 2N − 2 comb-like sharp resonant peaks also called transmission channels for N > 1 in transmission spectra in the absence and presence of an external magnetic field. Due to the coupling between evanescent waves and propagating modes in plasma and dielectric layers, respectively, 2N − 2 transmission channels are found without the addition of any defect, enabling the structure to work as a multichannel filter. Next, the filter properties can be made tunable by the application of an external magnetic field, i.e., channel frequency can either be red or blue shifted depending upon the orientation of an external magnetic field. The number of channels and their positions can also be modulated by changing the number of periods (N) and the incident angle (θo), respectively, for both transverse electric (TE) and transverse magnetic (TM) modes besides other parameters such as plasma collision frequency, thickness of the plasma layer, plasma frequency, etc.
1D kinetic simulations of a short glow discharge in helium
Authors: Yuan Chengxun , Bogdanov E. A. , Eliseev S. I. , Kudryavtsev A. A.
Published: July 2017

This paper presents a 1D model of a direct current glow discharge based on the solution of the kinetic Boltzmann equation in the two-term approximation. The model takes into account electron-electron coulomb collisions, the corresponding collision integral is written in both detailed and simplified forms. The Boltzmann equation for electrons is coupled with continuity equations for ions and metastable atoms and the Poisson equation for electric potential. Simulations are carried out self-consistently for the whole length of discharge in helium (from cathode to anode) for cases p = 1 Torr, L = 3.6 cm and p = 20 Torr, L = 1.8 mm, so that pL = 3.6 cm·Torr in both cases. It is shown that simulations based on the kinetic approach give lower values of electron temperature in plasma than fluid simulations. Peaks in spatial differential flux corresponding to the electrons originating from superelastic collisions and Penning ionization were observed in simulations. Different approaches of taking coulomb collisions into account give significantly different values of electron density and electron temperature in plasma. Analysis showed that using a simplified approach gives a non-zero contribution to the electron energy balance, which is comparable to energy losses on elastic and inelastic collisions and leads to significant errors and thus is not recommended.
A hybrid memory kernel approach for condensed phase non-adiabatic dynamics
Authors: Hait Diptarka , Mavros Michael G. , Van Voorhis Troy
Published: July 2017

The spin-boson model is a simplified Hamiltonian often used to study non-adiabatic dynamics in large condensed phase systems, even though it has not been solved in a fully analytic fashion. Herein, we present an exact analytic expression for the dynamics of the spin-boson model in the infinitely slow-bath limit and generalize it to approximate dynamics for faster baths. We achieve the latter by developing a hybrid approach that combines the exact slow-bath result with the popular non-interacting blip approximation (NIBA) method to generate a memory kernel that is formally exact to second-order in the diabatic coupling but also contains higher-order contributions approximated from the second-order term alone. This kernel has the same computational complexity as the NIBA, but is found to yield dramatically superior dynamics in regimes where the NIBA breaks down—such as systems with large diabatic coupling or energy bias. This indicates that this hybrid approach could be used to cheaply incorporate higher-order effects into second-order methods and could potentially be generalized to develop alternate kernel resummation schemes.
Highly conductive homoepitaxial Si-doped Ga2O3 films on (010) β-Ga2O3 by pulsed laser deposition
Authors: Leedy Kevin D. , Chabak Kelson D. , Vasilyev Vladimir , Look David C. , Boeckl John J. , Brown Jeff L. , Tetlak Stephen E. , Green Andrew J. , Moser Neil A. , Crespo Antonio , Thomson Darren B. , Fitch Robert C. , McCandless Jonathan P. , Jessen Gregg H.
Published: July 2017

Si-doped Ga2O3 thin films were fabricated by pulsed laser deposition on semi-insulating (010) β-Ga2O3 and (0001) Al2O3 substrates. Films deposited on β-Ga2O3 showed single crystal, homoepitaxial growth as determined by high resolution transmission electron microscopy and x-ray diffraction. Corresponding films deposited on Al2O3 were mostly single phase, polycrystalline β-Ga2O3 with a preferred (201¯) orientation. An average conductivity of 732 S cm−1 with a mobility of 26.5 cm2 V−1 s−1 and a carrier concentration of 1.74 × 1020 cm−3 was achieved for films deposited at 550 °C on β-Ga2O3 substrates as determined by Hall-Effect measurements. Two orders of magnitude improvement in conductivity were measured using native substrates versus Al2O3. A high activation efficiency was obtained in the as-deposited condition. The high carrier concentration Ga2O3 thin films achieved by pulsed laser deposition enable application as a low resistance ohmic contact layer in β-Ga2O3 devices.
Non-MHD effects in the nonlinear development of the MHD-scale Rayleigh-Taylor instability
Authors: Umeda Takayuki , Wada Yasutaka
Published: July 2017

The nonlinear evolution of the Rayleigh-Taylor instability (RTI) at a density shear layer transverse to magnetic field in a collisionless plasma is investigated by means of a fully kinetic Vlasov simulation with two spatial and two velocity dimensions. The primary RTI in the MHD regime develops symmetrically in a coordinate axis parallel to gravity as seen in the previous MHD simulations. The primary RTI in the Hall-MHD regime develops asymmetrically in a coordinate axis parallel to gravity. A compressible flow is formed at the secondary density shear layer by the Hall effect, which generates a strong scalar pressure gradient of ions. A Hall electric field due to the diamagnetic current results in the asymmetric flow at the tip of the finger structure. In the primary RTI with the ion gyro kinetic effect, secondary RTI with a wavelength shorter than the wavelength of the primary RTI is generated at the saturation stage of the primary RTI. A seed perturbation for the secondary RTI is excited by another secondary instability due to the coupling between the electron stress tensor and the Hall electric field. The heat flux term plays an important role in the time development of the total pressure. On the other hand, the contribution of the ion stress tensor is small in both the electric current and the total pressure.
Discharge characteristics of an ablative pulsed plasma thruster with non-volatile liquid propellant
Authors: Ling William Yeong Liang , Schönherr Tony , Koizumi Hiroyuki
Published: July 2017

Pulsed plasma thrusters (PPTs) are a form of electric spacecraft propulsion. They have an extremely simple structure and are highly suitable for nano/micro-spacecraft with weights in the kilogram range. Such small spacecraft have recently experienced increased growth but still lack suitable efficient propulsion systems. PPTs operate in a pulsed mode (one discharge = one shot) and typically use solid polytetrafluoroethylene (PTFE) as a propellant. However, new non-volatile liquids in the perfluoropolyether (PFPE) family have recently been found to be promising alternatives. A recent study presented results on the physical characteristics of PFPE vs. PTFE, showing that PFPE is superior in terms of physical characteristics such as its resistance to carbon deposition. This letter will examine the electrical discharge characteristics of PFPE vs. PTFE. The results demonstrate that PFPE has excellent shot-to-shot repeatability and a lower discharge resistance when compared with PTFE. Taken together with its physical characteristics, PFPE appears to be a strong contender to PTFE as a PPT propellant.
Density of topological constraints as a metric for predicting glass hardness
Authors: Zheng Qiuju , Yue Yuanzheng , Mauro John C.
Published: July 2017

Topological constraint theory has previously been applied to predict the composition dependence of glass hardness for a variety of different composition families. Some recent findings have cast doubt on the correlation between glass hardness and the number of rigid constraints per atom in silicate glasses. In this letter, we revisit the prediction of hardness for borosilicate and phosphosilicate glasses using four different types of constraint counting approaches: total number of constraints per atom, angular constraints per atom, total constraint density, and angular constraint density. We find that the counting approaches using total constraint density or angular constraint density give an improved prediction of glass hardness. We therefore conclude that glass hardness is governed by the density of rigid constraints under an indenter, rather than by the number of rigid constraints per atom.
Light induced degradation of Cu(In,Ga)Se2 thin film surfaces
Authors: Hölscher T. , Förster S. , Schneider T. , Maiberg M. , Widdra W. , Scheer R.
Published: July 2017

We investigate light-induced degradation of Cu(In,Ga)Se2 (CIGSe) layers by means of time-resolved photoluminescence (TRPL) measurements. Illumination in the range of minutes with 1 sun white light equivalent leads to a strong reduction of the carrier lifetime as determined by TRPL. Ambient storage in the dark, however, does not cause degradation. X-ray photoelectron spectroscopy of the CIGSe surface reveals a light induced enhancement of Na 1s and O 1s core-level emission. The position of the O 1s peak at 531.6 eV is related to a Na-O-CIGSe bonding complex. The light-induced degradation of the CIGSe layer finally translates into inferior open circuit voltages due to the dominance of interface recombination in completed solar cell devices. This study has implications for laboratory research and may need to be regarded in CIGSe module production.
Strong dopant dependence of electric transport in ion-gated MoS2
Authors: Piatti Erik , Chen Qihong , Ye Jianting
Published: July 2017

We report modifications of the temperature-dependent transport properties of MoS2 thin flakes via field-driven ion intercalation in an electric double layer transistor. We find that intercalation with Li+ ions induces the onset of an inhomogeneous superconducting state. Intercalation with K+ leads instead to a disorder-induced incipient metal-to-insulator transition. These findings suggest that similar ionic species can provide access to different electronic phases in the same material.
Computer vision uncovers predictors of physical urban change
Authors: Naik Nikhil , Kominers Scott Duke , Raskar Ramesh , Glaeser Edward L. , Hidalgo César A.
Published: July 2017

Significance

We develop a computer vision method to measure changes in the physical appearances of neighborhoods from street-level imagery. We correlate the measured changes with neighborhood characteristics to determine which characteristics predict neighborhood improvement. We find that both education and population density predict improvements in neighborhood infrastructure, in support of theories of human capital agglomeration. Neighborhoods with better initial appearances experience more substantial upgrading, as predicted by the tipping theory of urban change. Finally, we observe more improvement in neighborhoods closer to both city centers and other physically attractive neighborhoods, in agreement with the invasion theory of urban sociology. Our results show how computer vision techniques, in combination with traditional methods, can be used to explore the dynamics of urban change.
Contagious bovine pleuropneumonia - never out of Africa?
Authors: Olorunshola I. D. , Peters A. R. , Scacchia M. , Nicholas R. A. J.
Published: July 2017

Despite being eradicated from Europe and probably the rest of the world, contagious bovine pleuropneumonia (CBPP) continues to plague sub-Saharan Africa affecting at least 25 countries, in particular Ethiopia, Ghana, Tanzania, Cameroon, Angola, Nigeria and Zambia. Evidence has shown that the causative agent,
Mycoplasma mycoides
subsp.
mycoides
, may have emerged from a closely related goat pathogen as recently as 300 years ago, which corresponds to the first description of CBPP in Europe. Numerous new vaccines have been produced over the last 20 years in an effort to improve on the protection afforded by the T1/44, a live vaccine in continuous use in Africa for over 60 years but none have so far succeeded; indeed, many have exacerbated the condition. In this review, we argue that the present tools for diagnosis and control are adequate for eradication and what is necessary are resources to improve vaccine coverage to levels of at least 80%, last seen in the 1970s when CBPP was restricted to very few countries of Africa. In addition, a study in Namibia supported the concept that strategic and targeted antimicrobial treatment can play a critical part in the control alongside regular and comprehensive vaccination.
Effects of a phase change cooling garment during exercise in the heat
Authors: Butts Cory L. , Torretta Madeline L. , Smith Cody R. , Petway Adam J. , McDermott Brendon P.
Published: July 2017

The purpose of our study was to examine the physiological, perceptual, and performance effects of wearing a phase change cooling garment (CG) during an interval exercise routine in the heat. Sixteen male participants (age 23 ± 3 years, ht 1.76 ± 0.11 m; wt 78.5 ± 11.2 kg; body fat 15.2 ± 5.8%) completed two trials (one with phase change inserts, CG, and one control without inserts) consisting of two submaximal exercise portions separated by 5‐minute seated rest, and a final maximal effort performance bout. Each submaximal bout involved 30 seconds or 1 minute of muscular endurance and agility exercises and 5 minutes of treadmill jogging and step‐ups. The performance bout included 30 seconds or 1 minute of muscular endurance and agility exercises, with participants completing as many repetitions as possible, followed by a 15‐minute recovery (active and passive). Rectal temperature (Tre) and heart rate were not different between trials, however change in Tre from baseline was improved during 10 and 15 minutes of recovery with the CG (P < .05). Mean skin temperature was lower using the CG vs control throughout the trial (P < .05). Thermal sensation was lower when using the CG compared to control (P < .001). There were no differences in any outcomes of the performance exercises (P > .05). These findings indicate that the continuous use of a CG during an interval style workout in the heat provides improvements in thermal sensation, however, only minimal thermophysiological benefits, and no performance augmentation.
The role of customized vestibular rehabilitation with visual desensitization in the management of visual vertigo syndrome
Authors: Moaty Asmaa Salah , EL Mahallawi Trandil Hassan , Emara Afaf Ahmed , Talaat Hossam Sanyelbhaa , Zeinelabedeen Ahmed Mahmoud , Dimitriadis Panagiotis A. , Allam Ahmed , Bowes Christopher , Ray Jaydip
Published: July 2017

Objectives:

The objective of this study is to assess the benefits of customized vestibular rehabilitation with visual desensitization in the management of visual vertigo (VV).

Methods:

This retrospective study included 65 patients suffering from VV with situational characteristic questionnaire more than 0.9. Patients who did not complete the follow up in the VV clinic were not included in the analysis. Patients underwent customized vestibular rehabilitation using graded and progressive gaze stabilization exercises without background followed by introduction of visual stimulation (e.g. patterned wallpaper) and optokinetic DVD for home training to promote visual desensitization. The Situational Characteristic Questionnaire (SCQ), Hospital Anxiety and Depression Scale (HADS), the Nijmegen Questionnaire and Dizziness Handicap Inventory (DHI) were used to assess patient symptoms before and after the vestibular rehabilitation.

Results:

Seventy-five per cent of subjects in the study had statistically significant improvement in the SCQ from 2.31 ± 0.73 to 1.89 ± 0.88 after the rehabilitation. Sixty-three per cent of patients had statistically significant improvement in the Nijmegen questionnaire from 27.03 ± 9.94 to 24.75 ± 11.88 after the rehabilitation. There was statistically insignificant difference in the HADS score from 9.69 ± 4.28 to 9.76 ± 5.21 after the rehabilitation. Although there was improvement in the total DHI score as well (from 53.87 ± 16.289 to 50.10 ± 20.413), this was statistically insignificant. However, there was statistically significant improvement in the DHI some subgroups (physical and functional scores) and statistically non-significant improvement in other subgroups (emotional score and total score). The mean duration of rehabilitation was 6.8 ± 5 months. Correlation analysis between SCQ score and other questionnaire scores after the rehabilitation shows significant positive correlation between the post-rehabilitation SCQ questionnaire and other questionnaires.

Conclusions:

Customized vestibular rehabilitation incorporating visual desensitization exercises with optokinetic DVD results in significant improvement in VV symptoms.
Memory, art and the social condition
Authors: Goldfarb Jeffrey
Published: July 2017

Theodor Adorno once famously declared: ‘To write poetry after Auschwitz is barbaric’. An opposing proposition: without poetry, and more generally speaking, without the arts, we cannot successfully confront modern barbarism. This paper explores this opposing proposition by closely analysing three works of art and how they have made it possible to confront difficult pasts – Toni Morrison’s Beloved, Paweł Pawlikowski’s film, Ida, and Maya Lin’s Vietnam Veterans Memorial. The central argument of the paper is that it is particularly in the creation and appreciation of art that the challenges of memory (and forgetting), as important dilemmas knitted into the fabric of social life, ‘the social condition’, are successfully confronted.
Fuel Characterization of Newly Discovered Nigerian Coals
Authors: Bevan Nyakuma Bemgba , Oladokun Olagoke , Jauro Aliyu , Damian Nyakuma Denen
Published: July 2017

This study seeks to characterize and highlight the fuel properties, rank, and classification of coals from Ihioma (IHM) and Ogboligbo (OGB) in Imo and Kogi states of Nigeria, respectively. The fuel properties were examined based on ultimate, proximate, and bomb calorific analyses. The results indicated that IHM coal contains comparatively higher C and H but lower O, N, and S content than OGB. In addition, the nitrogen (N) and sulphur (S) content for both coal samples were above 0.7 wt.% and 1.5 wt.%, respectively, which indicates high potential for pollutant emissions. Furthermore, the coal proximate properties were below 5 wt.% for Moisture; Volatiles (70 wt.%); Fixed Carbon (45 wt.%) and Ash (2.5 wt.%) on average. IHM coal has an HHV of 19.40 MJ/kg whereas OGB is 15.55 MJ/kg. This is due to the low carbon (C), hydrogen (H) and high oxygen (O) content in OGB whereas IHM contains higher VM and HHV. Furthermore, OGB presents better handling, storage, and transport potential. Furthermore, OGB has a higher fuel ratio and value index due to lower moisture, ash content, and volatiles. Based on the ASTM D388 standard, the coals were classified as Lignite (Brown) Low-Rank Coals (LRCs) with potential for energy recovery.
Metrics 𝜌, quasimetrics 𝜌^{𝑠} and pseudometrics inf𝜌^{𝑠}
Authors: Storozhuk K. V.
Published: July 2017

Let

ρ
\rho

be a metric on a space

X
X

and let

s
≥
1

s\geq 1

. The function

ρ
s

(
a
,
b
)
=
ρ
(
a
,
b

)
s

\rho ^s(a,b)=\rho (a,b)^s

is a quasimetric (it need not satisfy the triangle inequality). The function

inf

ρ
s

(
a
,
b
)

\inf \rho ^s(a,b)

defined by the condition
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="inf rho Superscript s Baseline left-parenthesis a comma b right-parenthesis equals inf left-brace sigma-summation Underscript 0 Overscript n Endscripts rho Superscript s Baseline left-parenthesis z Subscript i Baseline comma z Subscript i plus 1 Baseline right-parenthesis">

inf

ρ
s

(
a
,
b
)
=
inf
{

∑
0
n

ρ
s

(

z
i

,

z

i
+
1

)

\inf \rho ^s(a,b)=\inf \{\sum _0^n \rho ^s(z_i,z_{i+1})

z
0

=
a
,

z
n

=
b
}

z_0=a, z_n=b\}

is a pseudometric (i.e., satisfies the triangle inequality but can be degenerate). We show how this degeneracy can be connected with the Hausdorff dimension of the space

(
X
,
ρ
)

(X,\rho )

. We also give some examples showing how the topology of the space 

(
X
,
inf

ρ
s

)

(X,\inf \rho ^s)

can change as

s
s

changes.
TeachEnG: a

Teach

ing

En

gine for

G

enomics
Authors: Kim Minji , Kim Yeonsung , Qian Lei , Song Jun S
Published: July 2017

Motivation

Bioinformatics is a rapidly growing field that has emerged from the synergy of computer science, statistics and biology. Given the interdisciplinary nature of bioinformatics, many students from diverse fields struggle with grasping bioinformatic concepts only from classroom lectures. Interactive tools for helping students reinforce their learning would be thus desirable. Here, we present an interactive online educational tool called TeachEnG (acronym for Teaching Engine for Genomics) for reinforcing key concepts in sequence alignment and phylogenetic tree reconstruction. Our instructional games allow students to align sequences by hand, fill out the dynamic programming matrix in the Needleman–Wunsch global sequence alignment algorithm, and reconstruct phylogenetic trees via the maximum parsimony, Unweighted Pair Group Method with Arithmetic mean (UPGMA) and Neighbor-Joining algorithms. With an easily accessible interface and instant visual feedback, TeachEnG will help promote active learning in bioinformatics.

Availability and implementation

TeachEnG is freely available at http://teacheng.illinois.edu. The source code is available from https://github.com/KnowEnG/TeachEnG under the Artistic License 2.0. It is written in JavaScript and compatible with Firefox, Safari, Chrome and Microsoft Edge.
Amyloidogenic medin induces endothelial dysfunction and vascular inflammation through the receptor for advanced glycation endproducts
Authors: Migrino Raymond Q. , Davies Hannah A. , Truran Seth , Karamanova Nina , Franco Daniel A. , Beach Thomas G. , Serrano Geidy E. , Truong Danh , Nikkhah Mehdi , Madine Jillian
Published: July 2017

Aims

Medin is a common amyloidogenic protein in humans that accumulates in arteries with advanced age and has been implicated in vascular degeneration. Medin’s effect on endothelial function remains unknown. The aims are to assess medin’s effects on human arteriole endothelial function and identify potential mechanisms underlying medin-induced vascular injury.

Methods and results

Ex vivo human adipose and leptomeningeal arterioles were exposed (1 h) to medin (0.1, 1, or 5 µM) without or with FPS–ZM1 [100 µM, receptor for advanced glycation endproducts (RAGE)-specific inhibitor] and endothelium-dependent function (acetylcholine dilator response) and endothelium-independent function (dilator response to nitric oxide donor diethylenetriamine NONOate) were compared with baseline control. Human umbilical vein endothelial cells were exposed to medin without or with FPS–ZM1 and oxidative and nitrative stress, cell viability, and pro-inflammatory signaling measures were obtained. Medin caused impaired endothelial function (vs. baseline response: −45.2 ± 5.1 and −35.8 ± 7.9% in adipose and leptomeningeal arterioles, respectively, each P < 0.05). Dilator response to NONOate was not significantly changed. Medin decreased arteriole and endothelial cell nitric oxide production, increased superoxide production, reduced endothelial cell viability, proliferation, and migration. Medin increased gene and protein expression of interleukin-6 and interleukin-8 via activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB). Medin-induced endothelial dysfunction and oxidative stress were reversed by antioxidant polyethylene glycol superoxide dismutase and by RAGE inhibitor FPS-ZM1.

Conclusions

Medin causes human microvascular endothelial dysfunction through oxidative and nitrative stress and promotes pro-inflammatory signaling in endothelial cells. These effects appear to be mediated via RAGE. The findings represent a potential novel mechanism of vascular injury.
An Analysis of the Complete Genome Sequence and Subgenomic RNAs Reveals Unique Features of the Ampelovirus, Grapevine leafroll-associated virus 1
Authors: Donda Bhanu Priya , Jarugula Sridhar , Naidu Rayapati A.
Published: July 2017

Despite being the first closterovirus documented in grapevines (Vitis sp.), the molecular biology of Grapevine leafroll-associated virus 1 (GLRaV-1, genus Ampelovirus, family Closteroviridae) is still in its infancy. In this study, the complete genome sequence of two GLRaV-1 isolates was determined to be 18,731 (isolate WA-CH) and 18,946 (isolate WA-PN) nucleotides (nt). The genome of WA-CH and WA-PN isolates encodes nine putative open reading frames (ORFs) and the arrangement of these ORFs in both isolates was similar to that of Australian and Canadian isolates. In addition to two divergent copies of the coat protein (CP), the genome of GLRaV-1 isolates contain CP-homologous domain in four genes, making the virus unique among Closteroviridae members. The 5′ and 3′ nontranslated regions (NTRs) of WA-CH and WA-PN isolates showed differences in size and sequence composition, with 5′ NTR having variable number of ∼65-nt-long repeats. Using the 5′ NTR sequences, a reverse transcription-polymerase chain reaction and restriction fragment length polymorphism method was developed to distinguish GLRaV-1 variants in vineyards. Northern analysis of total RNA from GLRaV-1-infected grapevine samples revealed three subgenomic RNAs (sgRNAs), corresponding tentatively to CP, p21, and p24 ORFs, present at higher levels, with p24 sgRNA observed at relatively higher abundance than the other two sgRNAs. The 5′ terminus of sgRNAs corresponding to CP, CPd1, CPd2, p21, and p24 were mapped to the virus genome and the leader sequence for these five sgRNAs determined to be 68, 27, 15, 49, and 18 nt, respectively. Taken together, this study provided a foundation for further elucidation of the comparative molecular biology of closteroviruses infecting grapevines.
Congenital Cytomegalovirus Among Children With Cerebral Palsy
Authors: Smithers-Sheedy Hayley , Raynes-Greenow Camille , Badawi Nadia , Fernandez Marian A. , Kesson Alison , McIntyre Sarah , Leung Kin-Chuen , Jones Cheryl A.
Published: July 2017

(Abstracted from J Pediatr 2017;181:267–271)

Congenital cytomegalovirus (cCMV) infection is estimated to affect approximately 0.7% of newborn infants, although only approximately 10% to 15% of these show signs of infection at birth. Infected infants face a heightened risk of permanent neurodevelopmental disability, including cerebral palsy (CP).
Emerging cancer-specific therapeutic aptamers
Authors: Yoon Sorah , Rossi John J.
Published: July 2017

Purpose of review

We will describe recently discovered smart aptamers with tumor specificity, with an emphasis on targeted delivery of novel therapeutic molecules, cancer-specific biomarkers, and immunotherapy.

Recent findings

The development of cancer-specific aptamers has facilitated targeted delivery of potent therapeutic molecules to cancer cells without harming nontumoral cells. This specificity also makes it possible to discover novel cancer biomarkers. Furthermore, alternative immune-checkpoint blockade aptamers have been developed for combinational immunotherapy.

Aptamers selected against cancer cells show cancer specificity, which has great potential for targeting. First, functionalizing targeted aptamers with therapeutic molecule payloads (e.g., small activating RNAs, antimitotic drugs, therapeutic antibodies, and peptides) facilitates successful delivery into cancer cells. This approach greatly improves the therapeutic index by minimizing side-effects in nontumoral cells. Second, cancer-specific proteins have been identified as cancer biomarkers through in-vitro and in-vivo selection, aptamer pull-down assays, and mass spectrometry. These newly discovered biomarkers improve therapeutic intervention and diagnostic specificity. In addition, the development of alternative immune-checkpoint blockade aptamers is suggested for use in combinational immunotherapeutic with current immune blockade regimens, to reduce the resistance and exhaustion of T cells in clinical trials.

Video abstract

http://links.lww.com/COON/A21.
Association between risk factors and detection of cutaneous melanoma in the setting of a population-based skin cancer screening
Authors: Hübner Joachim , Waldmann Annika , Eisemann Nora , Noftz Maria , Geller Alan C. , Weinstock Martin A. , Volkmer Beate , Greinert Rüdiger , Breitbart Eckhard W. , Katalinic Alexander
Published: July 2017

Early detection is considered to improve the prognosis of cutaneous melanoma. The value of population-based screening for melanoma, however, is still controversial. The aim of this study was to evaluate the predictive power of established risk factors in the setting of a population-based screening and to provide empirical evidence for potential risk stratifications. We reanalyzed data (including age, sex, risk factors, and screening results) of 354 635 participants in the Skin Cancer Research to provide Evidence for Effectiveness of Screening in Northern Germany (SCREEN)project conducted in the German state of Schleswig-Holstein (2003–2004). In multivariable analysis, atypical nevi [odds ratio (OR): 17.4; 95% confidence interval (CI): 14.4–20.1], personal history of melanoma (OR: 5.3; 95% CI: 3.6–7.6), and multiple (≥40) common nevi (OR: 1.3; 95% CI: 1.1–1.6) were associated with an increased risk of melanoma detection. Family history and congenital nevi were not significantly associated with melanoma detection in the SCREEN. The effects of several risk-adapted screening strategies were evaluated. Hypothesizing a screening of individuals aged more than or equal to 35 years, irrespective of risk factors (age approach), the number needed to screen is 559 (95% CI: 514–612), whereas a screening of adults (aged ≥20) with at least one risk factor (risk approach) leads to a number needed to screen of 178 (95% CI: 163–196). Converted into one screen-detected melanoma, the number of missed melanomas is 0.15 (95% CI: 0.12–0.18) with the age approach and 0.22 (95% CI: 0.19–0.26) with the risk approach. The results indicate that focusing on individuals at high risk for melanoma may improve the cost-effectiveness and the benefit-to-harm balance of melanoma screening programs.
Bioactivity and prostate tissue distribution of metformin in a preprostatectomy prostate cancer cohort
Authors: Nguyen Mike M. , Martinez Jessica A. , Hsu Chiu-Hsieh , Sokoloff Mitchell , Krouse Robert S. , Gibson Blake A. , Nagle Raymond B. , Parnes Howard L. , Cordova Catherine , Chow H-H. Sherry
Published: July 2017

Metformin has recently been shown to have potential to reduce prostate cancer risk. We conducted a randomized, double-blind, placebo-controlled trial to determine the modulating effects of metformin on tissue and systemic biomarkers of drug activity and its distribution into the prostate tissue. Twenty patients with prostate cancer scheduled to undergo prostatectomy were randomly assigned to receive either extended-release metformin or placebo for a median of 34 days before surgery. Prostatectomy and serum samples were analyzed for metformin concentrations, serum biomarkers of drug activity (prostate-specific antigen, insulin, insulin-like growth factor-1, insulin-like growth factor binding protein 3, sex hormone-binding globulin, and testosterone) and tissue biomarkers of proliferation, apoptosis, cell cycle regulation, and mTOR inhibition. For participants in the metformin arm, the prostate tissue and serum metformin concentrations ranged from 0.88 to 51.2 μg/g tissue and from not detectable to 3.6 μg/ml, respectively. There were no differences between the two groups in either the postintervention tissue biomarker expression in the prostatectomy tissue or pre to postintervention changes in serum biomarkers. We conclude that metformin distributes to human prostate tissue, suggesting that metformin could exert its effects directly on tissue targets. However, there was no difference in tissue and systemic drug effect biomarkers between the two treatment arms. Future studies with longer intervention duration and larger sample size should be considered in order to evaluate the potential of metformin for prostate cancer prevention.
Focal necrotizing myopathy with ‘dropped-head syndrome’ induced by cobimetinib in metastatic melanoma
Authors: Gauci Marie-Léa , Laly Pauline , Leonard-Louis Sarah , Behin Anthony , Gottlieb Jérémy , Madelaine-Chambrin Isabelle , Baroudjian Barouyr , Da-Meda Laetitia , Mourah Samia , Battistella Maxime , Basset-Seguin Nicole , Bagot Martine , Pages Cécile , Vercellino Laetitia , Maisonobe Thierry , Lebbé Céleste
Published: July 2017

Therapeutic advances derived from targeted therapy and immune checkpoint inhibitors can improve melanoma prognosis. Since 2015, cobimetinib has been approved in combination with vemurafenib in the first-line treatment for BRAF-mutated melanoma. For NRAS-mutated melanomas, MEK inhibition seems to be a therapeutic target, and association with checkpoint inhibitor provides a further therapeutic perspective. Infraclinical creatine phosphokinase (CPK) elevation is an MEK inhibitor side effect. We describe a case of focal necrotizing myopathy with ‘dropped-head syndrome’ induced by cobimetinib, 1 month after its introduction. The clinical presentation comprised interscapular pain, axial fatigue with cervical hypotonia, CPK elevation, intense fluorine-18-fluorodeoxyglucose uptake in cervical muscles, and necrotizing myopathy was confirmed by muscle biopsy. Cobimetinib was temporarily discontinued, resulting in CPK normalization. Re-evaluation showed partial response, motivating continuation of combination therapy with a reduced dose of cobimetinib (40 mg/day). Because prescription of targeted therapies is likely to increase, this adverse event should be known.
Children with Obsessive-Compulsive Symptomology in the General Population: Different Subtypes?
Authors: Zijlmans Josjan , Marhe Reshmi , van der Ende Jan , Verhulst Frank C. , Popma Arne , Tiemeier Henning , van den Heuvel Odile A.
Published: July 2017

Objective:

Obsessive-compulsive disorder (OCD) is a moderately prevalent neurodevelopmental disorder, and many children suffer from subclinical obsessive-compulsive (OC) symptoms. The disorder is heterogeneous and has high comorbidity rates. In early disease stages of psychiatric disorders, symptoms are typically hard to attribute exclusively to specific disorders. The authors investigated whether profiles of neuropsychiatric symptoms can be distinguished within a large population-based study of school-aged children (7–10 years) scoring high on OC symptoms.

Methods:

OC symptoms and comorbid symptoms common in pediatric OCD were assessed: symptoms of attention-deficit hyperactivity disorder, oppositional defiant disorder, autism, and anxiety. Latent profile analysis was performed on the subgroup of children scoring high on OC symptoms (high-OC sample, n = 209, i.e., 4.5% of total sample, n = 4632) using the z scores of the measures of comorbid symptoms as indicators.

Results:

Three distinguishable profiles were found within the high-OC sample. The first subgroup (“OC-specific”; 81.3%, 3.7% of total sample) had only OC-specific problems, the second subgroup (“Comorbid OC”; 11.0%, 0.5% of total sample) had high scores on all measures of comorbid symptomology, and the third subgroup (“Autistic OC”; 7.7%, 0.3%, of total sample) scored especially high on autism.

Conclusion:

The findings show that profiles based on neuropsychiatric symptoms can be distinguished within a population-based sample of school-aged children scoring high on obsessive-compulsive symptoms. These profiles may be useful in establishing patterns of symptom course during development. Longitudinal follow-up is necessary to ascertain whether at a later age these subgroups still differ in their symptom profile and neuropsychiatric trajectory.
Femtosecond Laser-Assisted Tuck-In Penetrating Keratoplasty for Advanced Keratoglobus With Endothelial Damage
Authors: Alió del Barrio Jorge L. , Al-Shymali Olena , Alió Jorge L.
Published: July 2017

Purpose:

To describe the outcomes of femtosecond laser-assisted tuck-in penetrating keratoplasty as a single-step surgical procedure for visual and anatomical rehabilitation of patients with severe keratoglobus (KTG) and endothelial damage.

Methods:

Two eyes of a 7-year-old patient with bilateral severe KTG and previous corneal hydrops were operated. Assisted by the femtosecond laser, both donor and recipient corneas were prepared. An 8.5-mm full-thickness donor tissue with a peripheral partial-thickness rim of 1.25 mm was sutured into an 8.5-mm recipient bed with a previously dissected intralamellar peripheral pocket up to the limbus. The graft was secured with 16 interrupted 10-0 nylon sutures and the peripheral donor rim tucked into the host stromal pocket.

Results:

Six months after surgery, both grafts remained healthy and clear. One eye developed mild postoperative ocular hypertension. No intraoperative or other postoperative complications were observed. Corrected distance visual acuity was 20/50 in both eyes, with complete functional rehabilitation of the patient. Restoration of the peripheral corneal thickness was observed in the pachymetric map.

Conclusions:

Femtosecond laser-assisted tuck-in penetrating keratoplasty can provide excellent anatomical and functional rehabilitation of patients with severe KTG and endothelial damage, through a single-step surgical procedure and a single donor cornea per eye. The femtosecond laser permits accurate dissection of these already thin corneas without inadvertent perforation risk.
Measuring Rates of Visual Field Progression in Linear Versus Nonlinear Scales: Implications for Understanding the Relationship Between Baseline Damage and Target Rates of Glaucoma Progression
Authors: Liebmann Kevin , De Moraes Carlos Gustavo , Liebmann Jeffrey M.
Published: July 2017

Purpose:

The purpose of this study is to test the hypothesis that the relationship between baseline visual field damage and the rate of progression depends upon the use of logarithmic (dB) versus linear (1/Lambert) scale.

Methods:

A total of 60 eyes (60 patients) with treated, established glaucoma and at least 5 reliable 24-2 visual fields were included. Baseline visual field mean deviation (MD) in dB was transformed to 1/Lambert using standard equation. Mixed effects linear regression was used to calculate the slopes (MD rates of progression over time) with linear and nonlinear scales. We tested the relationship between baseline MD and MD slopes for each scale of measure.

Results:

In dB scale, worse baseline visual field loss was associated with faster MD slopes (P=0.037), whereas the opposite effect was seen in 1/Lambert (P=0.001). For a similar rate of progression in dB/y, eyes with mild visual field damage lost more linear sensitivity over a given period of time than those with more severe baseline damage.

Conclusions:

There is a significant relationship between baseline visual field severity and rates of MD progression, although the direction of this association depends on the scale sensitivity is measured. The definition of fast versus slow visual field progression should be revised and take into account that sensitivity in linear scales show a better correlation with structural loss than when conventionally measured in nonlinear scale.
The Quantitative Measurements of Vascular Density and Flow Area of Optic Nerve Head Using Optical Coherence Tomography Angiography
Authors: Bazvand Fatemeh , Mirshahi Reza , Fadakar Kaveh , Faghihi Houshangh , Sabour Siamak , Ghassemi Fariba
Published: July 2017

Purpose:

The purpose of this study was to evaluate the vascular density (VD) and the flow area on optic nerve head (ONH) and peripapillary area, and the impact of age and sex using optical coherence tomography angiography (OCTA) in healthy human subjects.

Methods:

Both eyes of each volunteer were scanned by an RTVue XR Avanti; Optovue with OCTA using the split-spectrum amplitude-decorrelation angiography algorithm technique. Masked graders evaluated enface angiodisc OCTA data. The flow area of ONH and the VD were automatically calculated.

Results:

A total of 79 eyes of patients with a mean age of 37.03±11.27 were examined. The total ONH (papillary and peripapillary) area VD was 56.03%±4.55%. The flow area of the ONH was 1.74±0.10 mm2/1.34 mm2. The temporal and inferotemporal peripapillary VD was different between male and female patients. Increasing age causes some changes in the flow area of the ONH and the papillary VD from the third to the fourth decade (analysis of variance test; P<0.05).

Conclusions:

A normal quantitative database of the flow area and VD of the papillary and peripapillary area, obtained by RTVue XR with OCT angiography technique, is presented here.
Health Care Engagement and Follow-up After Perceived Discrimination in Maternity Care
Authors: Attanasio Laura , Kozhimannil Katy B.
Published: July 2017

Background:

Negative experiences in the health care system, including perceived discrimination, can result in patient disengagement from health care. Four million US women give birth each year, and the perinatal period is a time of sustained interaction with the health care system, but potential consequences of negative experiences have not been examined in this context. We assessed whether perceived discrimination during the birth hospitalization were associated with postpartum follow-up care.

Methods:

Data were from the Listening to Mothers III survey, a nationally drawn sample of 2400 women with singleton births in US hospitals in 2011–2012. We used multivariate logistic regression to estimate adjusted odds of having a postpartum visit in the 8 weeks following birth by perceptions of discrimination due to (1) race/ethnicity; (2) insurance type; and (3) a difference of opinion with a provider about care.

Results:

Women who experienced any of the 3 types of perceived discrimination had more than twice the odds of postpartum visit nonattendance (adjusted odds ratio=2.28, P=0.001), after adjusting for socioeconomic and medical characteristics.

Conclusions:

The postpartum visit is an opportunity for a patient and clinician to address continuing health problems following birth, discuss contraception, and screen for chronic disease. Forgoing this care may have negative health effects. The findings from this study underscore the need to reduce discrimination and improve maternity care experiences.
Fidget spinners: Purported benefits, adverse effects and accepted alternatives
Authors: Schecter Rachel A. , Shah Jay , Fruitman Kate , Milanaik Ruth Lynn
Published: July 2017

Purpose of review

In the span of a few months, fidget spinners have caught the eyes of millions of children, parents, educators and paediatricians. Fidget spinners, hand-held toys designed to spin freely in your grasp, have become a source of entertainment for consumers of all ages. Despite a lack of scientific evidence, toy marketers have advertised the benefits of fidget spinners for children with attention-deficit/hyperactivity disorder and other disorders (e.g. autism, anxiety, sensory issues). Parents are incentivized by these purported benefits to purchase fidget spinners to improve their child's concentration and decrease stress.

Recent findings

While fidget spinners are a new phenomenon, existing therapy toys (e.g. sensory putty) have been used by occupational therapists for similar reasons, with comparably little research supporting these claims. The purpose of this review is to explore literature regarding sensory toys and examine educator/professional-reported concerns and medical adverse effects of using fidget spinners.

Due to a recent surge in popularity, fidget spinners and other self-regulatory occupational therapy toys have yet to be subjected to rigorous scientific research. Thus, their alleged benefits remain scientifically unfounded. Paediatricians should be aware of potential choking hazards with this new fad, and inform parents that peer-reviewed studies do not support the beneficial claims.
Physical Activity Assessment During Gestation and Its Outcomes: A Review
Authors: Forczek Wanda , Curyło Marta , Forczek Barbara
Published: July 2017

Background

Physical activity recommendations emphasize a positive influence of exercise on health. It is particularly recognized during pregnancy for both the mother and fetus.

Aim

This review aims to identify the main trends of activity undertaken by women during gestation and to find out how it affects the expecting mother and her child.

Methods

Review of the literature comprising the following databases: PubMed, Academic Search Complete, Health Source—Consumer Edition, Health Source: Nursing/Academic Edition, EMBASE (2000 to May 2013), used detailed search strategies. The review was restricted to experimental studies. Trials were excluded if they met any of the following criteria: reviews, letters, commentaries or editorials, only abstracts available, and any kind of pathology during pregnancy. Three assessors reviewed the titles, abstracts, and full articles using standardized data abstraction forms, and they assessed the study quality. A total of 474 potential articles remained for analyses.

Findings

Twenty-eight articles were eligible for inclusion in the present review: randomized controlled trials and observational studies that evaluated maternal and offspring outcomes as a result of physical activity during pregnancy. Quasi-randomized trials were excluded. The activities that were most frequently assessed included occupational activity, housework/caregiving, sport/exercise, and active living, as well as habits. The authors evaluated different types of physical activity in the loading conditions. The aerobic activities most frequently used for assessment included treadmill walking program; step aerobics or stair stepper; aerobics; bicycle ergometer; combination of rowing, stationary cycling, and walk jogging; rhythmic calisthenics class and step class; brisk walks; stretching; and relaxation. The benefits following being active during pregnancy are associated with improved maternal psychological well-being, a reduced risk of preterm birth and excessive gestational weight gain, and lower risk of birth-related complications.

Conclusions

Patterns of activity change during pregnancy. Although exercise is safe for both the mother and fetus, most women reduce their activity level during the first weeks of gestation. Specifically, physical activity tends to be of lower duration, frequency, and intensity. Therefore, women should be encouraged by professionals to initiate or continue exercising during a healthy pregnancy.

Target Audience

Obstetricians and gynecologists, family physicians.

Learning Objectives

After completing this activity, the learner should be better able to identify the main trends among pregnant women in terms of physical activity, investigate the main benefits following exercising during pregnancy, recognize the most popular forms of physical activity in pregnant population, and realize health professionals to make women more aware of the importance of exercise.