bluuebunny/crossref_metadata_2025 huggingface dataset:
Construction of a coarse-grain quasi-classical trajectory method. II. Comparison against the direct molecular simulation method
Authors: Macdonald R. L. , Grover M. S. , Schwartzentruber T. E. , Panesi M.
Published: February 2018

This work presents the analysis of non-equilibrium energy transfer and dissociation of nitrogen molecules (N2(Σg+1)) using two different approaches: the direct molecular simulation (DMS) method and the coarse-grain quasi-classical trajectory (CG-QCT) method. The two methods are used to study thermochemical relaxation in a zero-dimensional isochoric and isothermal reactor in which the nitrogen molecules are heated to several thousand degrees Kelvin, forcing the system into strong non-equilibrium. The analysis considers thermochemical relaxation for temperatures ranging from 10 000 to 25 000 K. Both methods make use of the same potential energy surface for the N2(Σg+1)−N2(Σg+1) system taken from the NASA Ames quantum chemistry database. Within the CG-QCT method, the rovibrational energy levels of the electronic ground state of the nitrogen molecule are lumped into a reduced number of bins. Two different grouping strategies are used: the more conventional vibrational-based grouping, widely used in the literature, and energy-based grouping. The analysis of both the internal state populations and concentration profiles show excellent agreement between the energy-based grouping and the DMS solutions. During the energy transfer process, discrepancies arise between the energy-based grouping and DMS solution due to the increased importance of mode separation for low energy states. By contrast, the vibrational grouping, traditionally considered state-of-the-art, captures well the behavior of the energy relaxation but fails to consistently predict the dissociation process. The deficiency of the vibrational grouping model is due to the assumption of strict mode separation and equilibrium of rotational energy states. These assumptions result in errors predicting the energy contribution to dissociation from the rotational and vibrational modes, with rotational energy actually contributing 30%-40% of the energy required to dissociate a molecule. This work confirms the findings discussed in Paper I [R. L. Macdonald et al., J. Chem. Phys. 148, 054309 (2018)], which underlines the importance of rotational energy to the dissociation process, and demonstrates that an accurate non-equilibrium chemistry model must accurately predict the deviation of rovibrational distribution from equilibrium.
Ultra low-loss super-resolution with extremely anisotropic semiconductor metamaterials
Authors: Hart W. S. , Bak A. O. , Phillips C. C.
Published: February 2018

We investigate the mechanisms for the reduction of losses in doped semiconductor multilayers used for the construction of uniaxial metamaterials and show that maximizing the mean scattering time of the doped layers is key to spectrally isolating losses and maximizing anisotropy. By adjusting the layer thickness ratio of the multilayer, we show that the spectral regions of extreme anisotropy can be separated from those of high loss. Using these insights and coupled with realistic semiconductor growth parameters, we demonstrate an InAs-based superlens with an excellent loss factor α ≈ 52mm-1 and maximum perpendicular permittivity, ε⊥ > 250. By tuning the doping concentration, we show that such a system can be designed to operate anywhere in the region λ0 ≈ 5 to 25μm. We find that such a structure is capable of deep sub-wavelength imaging (< λ0/15) at superlens thicknesses up to ∼85μm (∼8λ0).
Enhanced ultraviolet photo-response in Dy doped ZnO thin film
Authors: Kumar Pawan , Singh Ranveer , Pandey Praveen C.
Published: February 2018

In the present work, a Dy doped ZnO thin film deposited by the spin coating method has been studied for its potential application in a ZnO based UV detector. The investigations on the structural property and surface morphology of the thin film ensure that the prepared samples are crystalline and exhibit a hexagonal crystal structure of ZnO. A small change in crystallite size has been observed due to Dy doping in ZnO. AFM analysis ascertains the grain growth and smooth surface of the thin films. The Dy doped ZnO thin film exhibits a significant enhancement in UV region absorption as compared to the pure ZnO thin film, which suggests that Dy doped ZnO can be used as a UV detector. Under UV irradiation of wavelength 325 nm, the photocurrent value of Dy doped ZnO is 105.54 μA at 4.5 V, which is 31 times greater than that of the un-doped ZnO thin film (3.39 μA). The calculated value of responsivity is found to increase significantly due to the incorporation of Dy in the ZnO lattice. The observed higher value of photocurrent and responsivity could be attributed to the substitution of Dy in the ZnO lattice, which enhances the conductivity, electron mobility, and defects in ZnO and benefits the UV sensing property.
A microfluidic device to study electrotaxis and dopaminergic system of zebrafish larvae
Authors: Peimani Amir Reza , Zoidl Georg , Rezai Pouya
Published: February 2018

The zebrafish is a lower vertebrate model organism offering multiple applications for both fundamental and biomedical research into the nervous system from genes to behaviour. Investigation of zebrafish larvae's movement in response to various stimuli, which involves the dopaminergic system, is of interest in the field of sensory-motor integration. Nevertheless, the conventional methods of movement screening in Petri dishes and multi-well plates are mostly qualitative, uncontrollable, and inaccurate in terms of stimulus delivery and response analysis. We recently presented a microfluidic device built as a versatile platform for fluid flow stimulation and high speed time-lapse imaging of rheotaxis behaviour of zebrafish larvae. Here, we describe for the first time that this microfluidic device can also be used to test zebrafish larvae's sense of the electric field and electrotaxis in a systemic manner. We further show that electrotaxis is correlated with the dopamine signalling pathway in a time of day dependent manner and by selectively involving the D2-like dopamine receptors. The primary outcomes of this research opens avenues to study the molecular and physiological basis of electrotaxis, the effects of known agonist and antagonist compounds on the dopaminergic system, and the screen of novel pharmacological tools in the context of neurodegenerative disorders. We propose that this microfluidic device has broad application potential, including the investigation of complex stimuli, biological pathways, behaviors, and brain disorders.
Ultrathin nanostructured solar selective absorber based on a two-dimensional hemispherical shell array
Authors: Chi Kequn , Yang Liu , He Sailing
Published: February 2018

A distinctive ultrathin nanostructured solar selective absorber is demonstrated experimentally. It consists of a self-assembled, two-dimensional, closely packed hexagonally distributed tungsten hemispherical shell array coated with an ultrathin germanium film (20 nm in thickness) and a silicon dioxide antireflective film. Due to the combined light trapping effects of unconventional interferences within the germanium film and the excited surface plasmon polaritons at the tungsten-germanium interface, as well as the antireflection effect of the silicon dioxide layer, the solar absorption of this absorber (0.93) is about as high as that of commercial black paint (0.94) and much higher than that of its planar counterpart (0.83). With greatly suppressed emission/absorption in the long wavelength range, its heat accumulation is superior, enabling a much higher temperature (218 °C under 7-sun illumination) than its planar counterpart and the black paint absorber (203 °C and 181 °C under 7-sun illumination, respectively).
Feed-forward coherent link from a comb to a diode laser: Application to widely tunable cavity ring-down spectroscopy
Authors: Gotti Riccardo , Prevedelli Marco , Kassi Samir , Marangoni Marco , Romanini Daniele
Published: February 2018

We apply a feed-forward frequency control scheme to establish a phase-coherent link from an optical frequency comb to a distributed feedback (DFB) diode laser: This allows us to exploit the full laser tuning range (up to 1 THz) with the linewidth and frequency accuracy of the comb modes. The approach relies on the combination of an RF single-sideband modulator (SSM) and of an electro-optical SSM, providing a correction bandwidth in excess of 10 MHz and a comb-referenced RF-driven agile tuning over several GHz. As a demonstration, we obtain a 0.3 THz cavity ring-down scan of the low-pressure methane absorption spectrum. The spectral resolution is 100 kHz, limited by the self-referenced comb, starting from a DFB diode linewidth of 3 MHz. To illustrate the spectral resolution, we obtain saturation dips for the 2ν3 R(6) methane multiplet at μbar pressure. Repeated measurements of the Lamb-dip positions provide a statistical uncertainty in the kHz range.
The flame characteristics of the biogas has produced through the digester method with various starters
Authors: Ketut Caturwati Ni , Agung Sudrajat , Mekro Permana , Heri Haryanto , Bachtiar
Published: February 2018

Increasing the volume of waste, especially in urban areas is a source of problems in realizing the comfort and health of the environment. It needs to do a good handling of garbage so as to provide benefits for the whole community. Organic waste processing through bio-digester method to produce a biogas as an energy source is an effort. This research was conducted to test the characteristics of biogas flame generated from organic waste processing through digester with various of the starter such as: cow dung, goat manure, and leachate that obtained from the landfill at Bagendung–Cilegon. The flame height and maximum temperature of the flame are measured for the same pressure of biogas. The measurements showed the flame produced by bio-digester with leachate starter has the lowest flame height compared to the other types of biogas, and the highest flame height is given by biogas from digester with cow dung as a starter. The maximum flame temperature of biogas produced by leachate as a starter reaches 1027 °C. This value is 7% lower than the maximum flame temperature of biogas produced by cow dung as a starter. Cow dung was observed to be the best starter compared to goat manure and leachate, but the use of leachate as a starter in producing biogas with biodigester method is not the best but it worked.
On an effective variation of Kronecker’s approximation theorem avoiding algebraic sets
Authors: Fukshansky Lenny , Moshchevitin Nikolay
Published: February 2018

Let

Λ
⊂

R

n

\Lambda \subset \mathbb R^n

be an algebraic lattice coming from a projective module over the ring of integers of a number field

K
K

. Let

Z

⊂

R

n

\mathcal Z \subset \mathbb R^n

be the zero locus of a finite collection of polynomials such that

Λ
⊈

Z

\Lambda \nsubseteq \mathcal Z

or a finite union of proper full-rank sublattices of

Λ
\Lambda

. Let

K
1

K_1

be the number field generated over

K
K

by coordinates of vectors in

Λ
\Lambda

, and let

L
1

,
…
,

L
t

L_1,\dots ,L_t

be linear forms in

n
n

variables with algebraic coefficients satisfying an appropriate linear independence condition over

K
1

K_1

. For each

ε
>
0

\varepsilon > 0

and

a
∈

R

n

\boldsymbol a \in \mathbb R^n

, we prove the existence of a vector

x
∈
Λ
∖

Z

\boldsymbol x \in \Lambda \setminus \mathcal Z

of explicitly bounded sup-norm such that

‖

L
i

(
x
)
−

a
i

‖
>
ε

\begin{equation*} \| L_i(\boldsymbol x) - a_i \| > \varepsilon \end{equation*}

for each

1
≤
i
≤
t

1 \leq i \leq t

, where

‖
 
‖

\|\ \|

stands for the distance to the nearest integer. The bound on sup-norm of

x
\boldsymbol x

depends on

ε
\varepsilon

, as well as on

Λ
\Lambda

,

K
K

,

Z

\mathcal Z

, and heights of linear forms. This presents a generalization of Kronecker’s approximation theorem, establishing an effective result on density of the image of

Λ
∖

Z

\Lambda \setminus \mathcal Z

under the linear forms

L
1

,
…
,

L
t

L_1,\dots ,L_t

in the

t
t

-torus 

R

t

/

Z

t

\mathbb R^t/\mathbb Z^t

.
𝐾-theory of line bundles and smooth varieties
Authors: Haesemeyer C. , Weibel C.
Published: February 2018

We give a

K
K

-theoretic criterion for a quasi-projective variety to be smooth. If

L

\mathbb {L}

is a line bundle corresponding to an ample invertible sheaf on

X
X

, it suffices that

K
q

(
X
)
≅

K
q

(

L

)

K_q(X)\cong K_q(\mathbb {L})

for all

q
≤
dim
⁡
(
X
)
+
1

q\le \dim (X)+1

.
Seshadri constants on hyperelliptic surfaces
Authors: Hanumanthu Krishna , Roy Praveen Kumar
Published: February 2018

We prove new results on single point Seshadri constants for ample line bundles on hyperelliptic surfaces, motivated by the results of Farnik [Arch. Math. 107 (2016), pp. 227–237]. Given a hyperelliptic surface

X
X

and an ample line bundle

L
L

on

X
X

, we show that the least Seshadri constant

ε
(
L
)

\varepsilon (L)

of

L
L

is a rational number when

X
X

is not of type 6. We also prove new lower bounds for the Seshadri constant

ε
(
L
,
1
)

\varepsilon (L,1)

of

L
L

at a very general point.
Avoiding algebraic integers of bounded house in orbits of rational functions over cyclotomic closures
Authors: Chen Evan
Published: February 2018

Let

k
k

be a number field with cyclotomic closure

k

c

k^{\mathrm {c}}

, and let

h
∈

k

c

(
x
)

h \in k^{\mathrm {c}}(x)

. For

A
≥
1

A \ge 1

a real number, we show that
\[

{
α
∈

k

c

:
h
(
α
)
∈

Z

¯

 has house at most 
A
}

\{ \alpha \in k^{\mathrm {c}} : h(\alpha ) \in \overline {\mathbb Z} \text { has house at most } A \}

\]
is finite for many

h
h

. We also show that for many such

h
h

the same result holds if

h
(
α
)

h(\alpha )

is replaced by orbits

h
(
h
(
⋯
h
(
α
)
)
)

h(h(\cdots h(\alpha )))

. This generalizes a result proved by Ostafe that concerns avoiding roots of unity, which is the case

A
=
1

A=1

.
On geodesic ray bundles in hyperbolic groups
Authors: Touikan Nicholas
Published: February 2018

We construct a Cayley graph

C
a
y

S

(
Γ
)

\mathbf {Cay}_{S}\left (\Gamma \right )

of a hyperbolic group

Γ
\Gamma

such that there are elements

g
,
h
∈
Γ

g,h\in \Gamma

and a point
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="gamma element-of partial-differential Subscript normal infinity Baseline normal upper Gamma equals partial-differential Subscript normal infinity Baseline bold upper C bold a bold y Subscript upper S Baseline left-parenthesis normal upper Gamma right-parenthesis">

γ
∈

∂

∞

Γ
=

∂

∞

C
a
y

S

(
Γ
)

\gamma \in \partial _{\infty }\Gamma = \partial _{\infty }\mathbf {Cay}_{S}\left (\Gamma \right )

such that the sets

R

B

(
g
,
γ
)

\mathcal {R}\mathcal {B}\left (g,\gamma \right )

and

R

B

(
h
,
γ
)

\mathcal {R}\mathcal {B}\left (h,\gamma \right )

in

C
a
y

S

(
Γ
)

\mathbf {Cay}_{S}\left (\Gamma \right )

of vertices along geodesic rays from

g
,
h

g,h

to

γ
\gamma

have infinite symmetric difference, thus answering a question of Huang, Sabok, and Shinko.
Relatively weakly open convex combinations of slices
Authors: Abrahamsen Trond , Lima Vegard
Published: February 2018

We show that

c
0

c_0

and, in fact,

C
(
K
)

C(K)

for any scattered compact Hausdorff space

K
K

have the property that finite convex combinations of slices of the unit ball are relatively weakly open.
GSK3β Modulates Timing-Dependent Long-Term Depression Through Direct Phosphorylation of Kv4.2 Channels
Authors: Aceto Giuseppe , Re Agnese , Mattera Andrea , Leone Lucia , Colussi Claudia , Rinaudo Marco , Scala Federico , Gironi Katia , Barbati Saviana Antonella , Fusco Salvatore , Green Thomas , Laezza Fernanda , D’Ascenzo Marcello , Grassi Claudio
Published: February 2018

Spike timing-dependent plasticity (STDP) is a form of activity-dependent remodeling of synaptic strength that underlies memory formation. Despite its key role in dictating learning rules in the brain circuits, the molecular mechanisms mediating STDP are still poorly understood. Here, we show that spike timing-dependent long-term depression (tLTD) and A-type K+ currents are modulated by pharmacological agents affecting the levels of active glycogen-synthase kinase 3 (GSK3) and by GSK3β knockdown in layer 2/3 of the mouse somatosensory cortex. Moreover, the blockade of A-type K+ currents mimics the effects of GSK3 up-regulation on tLTD and occludes further changes in synaptic strength. Pharmacological, immunohistochemical and biochemical experiments revealed that GSK3β influence over tLTD induction is mediated by direct phosphorylation at Ser-616 of the Kv4.2 subunit, a molecular determinant of A-type K+ currents. Collectively, these results identify the functional interaction between GSK3β and Kv4.2 channel as a novel mechanism for tLTD modulation providing exciting insight into the understanding of GSK3β role in synaptic plasticity.
Patterns of plant and animal protein intake are strongly associated with cardiovascular mortality: the Adventist Health Study-2 cohort
Authors: Tharrey Marion , Mariotti François , Mashchak Andrew , Barbillon Pierre , Delattre Maud , Fraser Gary E
Published: February 2018

Background

Current evidence suggests that plant and animal proteins are intimately associated with specific large nutrient clusters that may explain part of their complex relation with cardiovascular health. We aimed at evaluating the association between specific patterns of protein intake with cardiovascular mortality.

Methods

We selected 81 337 men and women from the Adventist Health Study-2. Diet was assessed between 2002 and 2007, by using a validated food frequency questionnaire. Dietary patterns based on the participants’ protein consumption were derived by factor analysis. Cox regression analysis was used to estimate multivariate-adjusted hazard ratios (HRs) adjusted for sociodemographic and lifestyle factors and dietary components.

Results

There were 2276 cardiovascular deaths during a mean follow-up time of 9.4 years. The HRs for cardiovascular mortality were 1.61 [98.75% confidence interval (CI), 1.12 2.32; P-trend < 0.001] for the ‘Meat’ protein factor and 0.60 (98.75% CI, 0.42 0.86; P-trend < 0.001) for the ‘Nuts & Seeds’ protein factor (highest vs lowest quintile of factor scores). No significant associations were found for the ‘Grains’, ‘Processed Foods’ and ‘Legumes, Fruits & Vegetables’ protein factors. Additional adjustments for the participants’ vegetarian dietary pattern and nutrients related to cardiovascular disease outcomes did not change the results.

Conclusions

Associations between the ‘Meat’ and ‘Nuts & Seeds’ protein factors and cardiovascular outcomes were strong and could not be ascribed to other associated nutrients considered to be important for cardiovascular health. Healthy diets can be advocated based on protein sources, preferring low contributions of protein from meat and higher intakes of plant protein from nuts and seeds.
Hadronic model for the non-thermal radiation from the binary system AR Scorpii
Authors: Bednarek W
Published: February 2018

AR Scorpii is a close binary system containing a rotation powered white dwarf and a low-mass M type companion star. This system shows non-thermal emission extending up to the X-ray energy range. We consider hybrid (lepto-hadronic) and pure hadronic models for the high energy non-thermal processes in this binary system. Relativistic electrons and hadrons are assumed to be accelerated in a strongly magnetised, turbulent region formed in collision of a rotating white dwarf magnetosphere and a magnetosphere/dense atmosphere of the M-dwarf star. We propose that the non-thermal X-ray emission is produced either by the primary electrons or the secondary e± pairs from decay of charged pions created in collisions of hadrons with the companion star atmosphere. We show that the accompanying γ-ray emission from decay of neutral pions, which are produced by these same protons, is expected to be on the detectability level of the present and/or the future satellite and Cherenkov telescopes. The γ-ray observations of the binary system AR Sco should allow us to constrain the efficiency of hadron and electron acceleration and also the details of the radiation processes.
What to Do About the Transition to Residency? Exploring Problems and Solutions From Three Perspectives
Authors: O’Brien Bridget C.
Published: February 2018

Transitions are both a blessing and a curse for learning and professional development. While transitions can afford valuable opportunities for growth, they can also burden learners in ways that stymie performance and development. In this Invited Commentary, the author focuses on the transition from medical school to residency—a transition that many believe has tipped too far toward burden. The commentary explores three ways of problematizing the transition to residency. The first is as a transaction problem involving a complex exchange of information among programs and people. The second is as a transfer problem in which learners must apply knowledge in new contexts. The third is a trajectory problem concerning each learner’s progression through medical education. The author describes current efforts aligned with each framing of the problem and discusses potential gaps in these efforts that might be addressed through an overarching framing of transitions in medical education as transformative processes. This framing may help the medical educational community think more holistically about the problems and solutions with transitions.
Characteristics of Successful Internal Medicine Resident Research Projects: Predictors of Journal Publication Versus Abstract Presentation
Authors: Atreya Auras R. , Stefan Mihaela , Friderici Jennifer L. , Kleppel Reva , Fitzgerald Janice , Rothberg Michael B.
Published: February 2018

Purpose

To identify the characteristics of successful research projects at an internal medicine residency program with an established research curriculum.

Method

The authors collected data about all research projects initiated by or involving medicine residents from 2006 to 2013 at Baystate Medical Center, using departmental files and institutional review board applications. Resident and mentor characteristics were determined using personnel files and Medline searches. Using multivariable models, the authors identified predictors of successful completion of projects using adjusted prevalence ratios (PRs). The primary outcome was manuscript publication, and secondary outcome was publication or regional/national presentation. Finally, residents were surveyed to identify barriers and/or factors contributing to project completion.

Results

Ninety-four research projects were identified: 52 (55.3%) projects achieved the primary outcome and 72 (76.5%) met the secondary outcome, with overlap between categories. Most study designs were cross-sectional (41; 43.6%) or retrospective cohort (30; 31.9%). After adjustment, utilization of the epidemiology/biostatistical core (PR = 2.09; 95% CI: 1.36, 3.21), established publication record of resident (PR = 1.54; 95% CI: 1.14, 2.07), and resident with U.S. medical education (PR = 1.39; 95% CI: 1.02, 1.90) were associated with successful project completion. Mentor publication record (PR = 3.13) did not retain significance because of small sample size. Most respondents (65%) cited “lack of time” as a major project barrier.

Conclusions

Programs seeking to increase resident publications should consider an institutional epidemiology/biostatistical core, made available to all residency research projects, and residents should choose experienced mentors with a track record of publications.
Intraoperative Neurophysiological Monitoring in Spine Surgery
Authors: Daniel Jefferson Walter , Botelho Ricardo Vieira , Milano Jerônimo Buzetti , Dantas Fernando Rolemberg , Onishi Franz Jooji , Neto Eloy Rusafa , Bertolini Eduardo de Freitas , Borgheresi Marcelo Antonio Duva , Joaquim Andrei Fernandes
Published: February 2018

Study Design.

Systematic literature review and meta-analysis.

Objective.

The objective of this systematic literature review was to evaluate if intraoperative neurophysiological monitoring (IONM) can prevent neurological injury during spinal operative surgical procedures.

Summary of Background Data.

IONM seems to have presumable positive effects in identifying neurological deficits. However, the role of IONM in the decrease of new neurological deficits remains unclear.

Methods.

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews and Meta-analysis, we reviewed clinical comparative studies who evaluate the rate of new neurological events in patients who had a spinal surgery with and without IONM. Studies were then classified according to their level of evidence. Methodological quality was assessed according to methodological index for non-randomized studies instrument.

Results.

Six studies were evaluated comparing neurological events with and without IONM use by the random effects model. There was a great statistical heterogeneity. The pooled odds ratio (OR) was 0.72 {0.71; 1.79}, P = 0.4584. A specific analysis was done for two studies reporting the results of IONM for spinal surgery of intramedullary lesions. The OR was 0.1993 (0.0384; 1.0350), P = 0.0550.

Conclusion.

IONM did not result into fewer neurological events with the obtained evidence of the included studies. For intramedullary lesions, there was a trend to fewer neurological events in patients who underwent surgery with IONM. Further prospective randomized studies are necessary to clarify the indications of IONM in spinal surgeries.

Level of Evidence: 2
Nicotinamide N-methyltransferase: potential involvement in cutaneous malignant melanoma
Authors: Ganzetti Giulia , Sartini Davide , Campanati Anna , Rubini Corrado , Molinelli Elisa , Brisigotti Valerio , Cecati Monia , Pozzi Valentina , Campagna Roberto , Offidani Annamaria , Emanuelli Monica
Published: February 2018

Nicotinamide N-methyltransferase (NNMT) is an enzyme that catalyzes the N-methylation of nicotinamide and pyridine compounds, participating in xenobiotic and drug metabolism. Data on literature have evidenced a possible role of NNMT in many solid cancers, but no data are currently available in cutaneous melanoma. Recent important advances have been achieved in the treatment of advanced melanoma with targeted therapy and immunotherapy. However, the identification of biomarkers that can be used for the detection of early stage disease as well as for monitoring the therapeutic response during treatment is of utmost importance. The aim of this study was to study the possible role of NNMT in melanoma. In the present study, we carried out immunohistochemical analyses to evaluate the expression of the enzyme NNMT in 34 melanomas and 34 nevi. Moreover, we explored the relationship between NNMT levels and the prognostic parameters of patients with melanoma. The results obtained showed significantly (P<0.0001) higher NNMT expression in melanoma compared with that detected in nevi. In addition, a significant (P<0.05) inverse relationship was found between enzyme levels and Breslow thickness, Clark level, the presence/number of mitoses, and ulceration. Taken together, these data seem to suggest that NNMT could represent a molecular biomarker for melanoma, thus highlighting its potential for both diagnosis and prognosis of this neoplasm.
Development and Validation of a Bioanalytical Method to Quantitate Enzalutamide and its Active Metabolite N-Desmethylenzalutamide in Human Plasma: Application to Clinical Management of Patients With Metastatic Castration–Resistant Prostate Cancer
Authors: Benoist Guillemette E. , van der Meulen Eric , van Oort Inge M. , Beumer Jan H. , Somford Diederik M. , Schalken Jack A. , Burger David M. , van Erp Nielka P.
Published: February 2018

Background:

Enzalutamide is a potent androgen-signaling receptor inhibitor and is licensed for the treatment of metastatic castration–resistant prostate cancer. N-desmethylenzalutamide is the active metabolite of enzalutamide. A method to quantitate enzalutamide and its active metabolite was developed and validated according to the European Medicine Agency guidelines.

Methods:

Enzalutamide and N-desmethylenzalutamide were extracted by protein precipitation, separated on a C18 column with gradient elution and analyzed with tandem quadrupole mass spectrometry in positive ion mode. A stable deuterated isotope (D6-enzalutamide) was used as an internal standard. The method was tested and stability was studied in real-life patients with metastatic castration–resistant prostate cancer patients treated with enzalutamide.

Results:

The calibration curve covered the range of 500–50,000 ng/mL. Within- and between-day precisions were <8% and accuracies were within 108% for both enzalutamide and N-desmethylenzalutamide. Precisions for lower limit of quantification level were <10% and accuracies within 116% for enzalutamide and N-desmethylenzalutamide. Enzalutamide and N-desmethylenzalutamide stability was proven for 24 hours for whole blood at ambient temperature and 23 days for plasma at both ambient temperature and 2–8°C. Long-term patient plasma stability was shown for 14 months at −40°C.

Conclusions:

This bioanalytical method was successfully validated and applied to determine plasma concentrations of enzalutamide and N-desmethylenzalutamide in clinical studies and in routine patient care.
Assessment of extent and completeness of mesorectal excision for rectal cancer by histopathology and MRI
Authors: Hassan Tajamul , Parray Fazl Q. , Rasool Zubaida , Chowdri Nisar A. , Shaheen Feroze A. , Wani Rauf A.
Published: February 2018

Introduction:

High quality of total mesorectal excision (TME) surgical technique and critical feedback regarding its completeness by pathologist and a radiologist has been shown to influence the quality of surgery in patients with rectal cancer. In this study, we tried to audit the quality of TME by 2 independent observers, a consultant pathologist and radiologist. TME was performed for all patients with rectal tumors located <12 cm from the anal verge.

Main Outcome Measures:

TME specimens were examined for completeness by experienced single consultant pathologist to avoid interobserver bias. Postoperatively magnetic resonance imaging was done that was interpreted by a single consultant radiologist to avoid interobserver bias in the study.

Discussion:

Of total 103 patients, TME assessment was done in 53 patients. TME was complete in 35 cases (66%), near complete in 14 cases (26%), and incomplete in 4 cases (8%) (P<0.05). Twenty-eight cases were subjected to radiologic assessment of TME. Complete TME was found in 19 (67%) and residual mesorectum was found in 9 (32%). The radiologic findings co-related with pathology findings in these 28 cases as 17 cases were confirmed TME complete by both magnetic resonance imaging and histopathology, 4 cases were confirmed incomplete by both and out of 7 near complete TME by pathology, 2 were labeled as complete on radiology while 5 were labeled as incomplete (P<0.05). Seven (13.2%) cases had positive circumferential resection margin. Distal resection margin was >2 cm in about 81.1%, <2 cm in 15% and involved in 3.7% of cases. The lymph node yield was of 4–21 with an average of 11.5 nodes; with 54.7% having adequate nodal harvest (>12 lymph nodes).

Conclusions:

Pathologist’s and radiologist’s constructive criticism will always help a surgeon to improve his quality of TME.
High-dose Chemotherapy is Efficacious and Well Tolerated in a Toddler With Aicardi Syndrome and Malignant Sacrococcygeal Teratoma
Authors: Wharton Jessica D. , Johnson Shaina , Connelly James A. , Hills Tracy , Gingles Lauren , Wood Margaret , Crane Gabriella L. , Katzenstein Howard M.
Published: February 2018

Aicardi syndrome (AS) is a rare neurodevelopmental disorder, predominantly seen in female individuals, which appears to have an increased risk of both benign and malignant neoplasia. We report the case of a child with AS who presented with metastatic malignant sacrococcygeal tumor (with yolk sac elements) which recurred and then was treated with 3 cycles of high-dose chemotherapy with autologous stem cell rescue. The patient tolerated therapy with acceptable toxicity and remains in clinical remission 3 months after the completion of therapy. Her neurological status remains similar to that before diagnosis with the exception of chemotherapy induced hearing loss. This is the first description a sacrococcygeal teratoma in a patient with Aicardi, as well as the first use of intensified consolidation chemotherapy in a patient with Aicardi, which was well tolerated and resulted in remission. The use of chemotherapy should be considered for all patients with AS and malignancy.
Mutation Screening of the Krüppel-like Factor 1 Gene in Individuals With Increased Fetal Hemoglobin Referred for Hemoglobinopathy Investigation in South of Iran
Authors: Hamid Mohammad , Ershadi Oskouei Sanaz , Shariati Gholamreza , Babaei Esmaeil , Galehdari Hamid , Saberi Alihossein , Sedaghat Alireza
Published: February 2018

Background:

Any mutation in the Krüppel-like factor 1 (KLF1) gene may interfere with its proper related function in the erythropoiesis process and lead to alterations in proper activation of its downstream protein through globin switching, which results in an increase in fetal hemoglobin (HbF). This study aimed to investigate whether KLF1 mutation can associate with high level of HbF in individuals with increased fetal hemoglobin referred for screening of hemoglobinopathies in south of Iran.

Materials and Methods:

The human KLF1 gene was amplified via the polymerase chain reaction procedure, and sequencing was used to determine any mutation in these patients. Moreover, XmnI polymorphisms in the position of −158 of γ-globin gene promoter were analyzed in all patients by polymerase chain reaction restriction fragment length polymorphism.

Result:

Analysis of sequencing revealed a missense mutation in the KLF1 gene, p.Ser102Pro (c.304T>C), which was detectable in 10 of 23 cases with elevated HbF level. This mutation was only detected in individuals who had a HbF level between 3.1% and 25.6%. Statistical analysis showed that the frequency of C allele is significantly correlated with a high level of HbF (P<0.05). The allele frequency of positive result of XmnI polymorphism in individuals with increased HbF level was also significant, which showed an association with increased HbF level (P<0.05).

Conclusions:

To the best of our knowledge, this is the first report of p.Ser102Pro (c.304T>C) in the KLF1 gene in β-thalassemia patients with increased level of fetal hemoglobin. According to statistical results of p.Ser102Pro mutation and XmnI polymorphism, it has been strongly suggested that both polymorphisms have an association with increased HbF samples. These nucleotide changes alone may not be the only elements raising the level of HbF, and other regulatory and modifying factors also play a role in HbF production.
Recent Abacavir Use Increases Risk of Type 1 and Type 2 Myocardial Infarctions Among Adults With HIV
Authors: Elion Richard A. , Althoff Keri N. , Zhang Jinbing , Moore Richard D. , Gange Stephen J. , Kitahata Mari M. , Crane Heidi M. , Drozd Daniel R. , Stein James H. , Klein Marina B. , Eron Joseph J. , Silverberg Michael J. , Mathews William C. , Justice Amy C. , Sterling Timothy R. , Rabkin Charles S. , Mayor Angel M. , Klein Daniel B. , Horberg Michael A. , Bosch Ronald J. , Eyawo Oghenowede , Palella Frank J. ,   for the North American AIDS Cohort Collaboration on Research and Design of IeDEA
Published: February 2018

Background:

There is persistent confusion as to whether abacavir (ABC) increases the risk of myocardial infarction (MI), and whether such risk differs by type 1 (T1MI) or 2 (T2MI) MI in adults with HIV.

Methods:

Incident MIs in North American Cohort Collaboration on Research and Design participants were identified from 2001 to 2013. Discrete time marginal structural models addressed channeling biases and time-dependent confounding to estimate crude hazard ratio (HR) and adjusted hazard ratio (aHR) and 95% confidence intervals; analyses were performed for T1MI and T2MI separately. A sensitivity analysis evaluated whether Framingham risk score (FRS) modified the effect of ABC on MI occurrence.

Results:

Eight thousand two hundred sixty-five adults who initiated antiretroviral therapy contributed 29,077 person-years and 123 MI events (65 T1MI and 58 T2MI). Median follow-up time was 2.9 (interquartile range 1.4–5.1) years. ABC initiators were more likely to have a history of injection drug use, hepatitis C virus infection, hypertension, diabetes, impaired kidney function, hyperlipidemia, low (<200 cells/mm3) CD4 counts, and a history of AIDS. The risk of the combined MI outcome was greater for persons who used ABC in the previous 6 months [aHR = 1.84 (1.17–2.91)]; and persisted for T1MI (aHR = 1.62 [1.01]) and T2MI [aHR = 2.11 (1.08–4.29)]. FRS did not modify the effect of ABC on MI (P = 0.14) and inclusion of FRS in the MSM did not diminish the effect of recent ABC use on the combined outcome.

Conclusions:

Recent ABC use was associated with MI after adjustment for known risk factors and for FRS. However, screening for T1MI risks may not identify all or even most persons at risk of ABC use-associated MIs.
Heritability of Facial Skeletal and Dental Characteristics of Monozygotic and Dizygotic Twins Using Cephalometric Analysis and Falconer's Method
Authors: Kim Eungmin , Sung Joohon , Song Yun-Mi , Chae Hwa Sung , Mo Sung-Seo , Kim Young Ho , Baek Seung-Hak
Published: February 2018

The purpose of this study was to investigate the heritability of facial skeletal and dental characteristics of the monozygotic (MZ) and dizygotic (DZ) twins. The samples consisted of Korean MZ and DZ twins (n = 13 pairs/each twin; 7 pairs of males and 6 pairs of females; mean age, 39 years, respectively). The linear, angular, and ratio variables, which could describe the size and shape of the facial horizontal and vertical, dental, mandible and cranial base structure, were measured. The Falconer's method was used to calculate the heritability (h2; close to or below 0, low heritability; close to or above 1, high heritability). In the facial horizontal and vertical aspects, the highest h2 values were shown at SNA (degree, 1.53), SNB (degree, 2.12), SN-Pog (degree, 2.19), SN-palatal plane angle (degree, 1.29), SN-mandibular plane angle (degree, 1.59), N-ANS/ANS-Me (1.66), and ANS-Me/N-Me (1.62). In the dental aspects, although L1-occlusal plane angle (degree, 1.38) and SN-occlusal plane angle (degree, 2.09) showed high h2 values, most of the dental variables showed low h2 values. In the mandible and cranial base, lower gonial angle, mandibular body length, and cranial base angle showed high h2 values (N-Go-Gn [degree], 1.07; Go-Pog [mm], 0.92; N-S-Ba [degree], 1.51). The descending order of the overall mean h2 values was the facial horizontal (1.10), facial vertical (0.71), mandible (0.59), cranial base (0.37), and dental characteristics (−0.11). The shape of facial skeletal structure and location of the occlusal plane within skeletal framework was more influenced by genetic factors than environmental factors.
Caesium neodymium sulfate, CsNd(SO4)2
Authors: Missen Owen Peter , Mills Stuart James , Petříček Vaclav
Published: February 2018

The crystal structure of caesium neodymium(III) sulfate, CsNd(SO4)2, was determined from intensity data collected on a Rigaku tabletop XtaLAB mini II diffractometer at the International Union of Crystallography Congress 2017, in Hyderabad, India. CsNd(SO4)2is the fourth crystal structure to be reported in the CsPr(SO4)2family: the Cs and Nd atoms have site symmetries of 2.. and ..2, respectively. In the extended structure, NdO8square antiprisms and SO4tetrahedra are connected into layers, which propagate in the (101) plane and CsO14polyhedra connect the layers into a three-dimensional network.
2,6,10-Trichlorotris[1,2,4]triazolo[1,5-a:1′,5′-c:1′′,5′′-e][1,3,5]triazine
Authors: Limbach Daniel , Detert Heiner , Schollmeyer Dieter
Published: February 2018

Three very similar and nearly planar molecules are present in the asymmetric unit of the title compound, C6Cl3N9. Whereas the threefold 1,5-annulation of the chlorotriazole moieties is obvious, all of the C and N atoms in the central triazine ring are equally disordered on the same site, approachingD3hsymmetry for each of the molecules.
Crystal structure of ω-Al4Cr
Authors: Fan Changzeng , Liu Cong
Published: February 2018

The new polymorph of tetraaluminium chromium, Al4Cr, designated as the ω-phase, was obtained as the product from a high-pressure sintering (HPS) process of a stoichiometric Al4Cr mixture. The crystal structure is isotypic with Al4Mo and Al4W. The unit cell of ω-Al4Cr is much smaller than any of the other reported Al4Cr polymorphs, containing 30 rather than several hundred atoms.
Corporate governance mechanisms and accounting conservatism: evidence from Egypt
Authors: Nasr Mahmoud A. , Ntim Collins G.
Published: February 2018

Purpose

The purpose of this paper is to investigate the effect of corporate governance (CG) mechanisms (board size, board independence, separation of chairman and chief executive officer (CEO) roles and external auditor type) on accounting conservatism in Egypt.

Design/methodology/approach

Archival data relating to CG and accounting conservatism are collected and analysed using multivariate regression techniques.

Findings

The findings indicate that board independence is positively associated with accounting conservatism. By contrast, board size and auditor type are negatively associated with accounting conservatism, while separating the chairperson and CEO roles has no significant relationship with accounting conservatism.

Originality/value

To the best of the author’s knowledge, this is one of the first empirical attempts at providing evidence on the relationship between CG and accounting conservatism in Egypt.
An integrative approach to HRM–firm performance relationship: a missing link to corporate governance
Authors: Petrovic Jelena , Saridakis George , Johnstone Stewart
Published: February 2018

Purpose

The purpose of this paper is to contribute to ongoing debates regarding the human resource management (HRM)-firm performance relationship. In seeking to provide a more complete picture of the relationship, the paper discusses the existing literature and proposes an integrative framework that draws upon different literatures and multiple theoretical perspectives.

Design/methodology/approach

This review includes nearly 100 research studies published in this field. The review includes papers published in mainstream HRM journals and broader management journals with strong ties to HRM literature. Importantly, the paper also identifies a gap – a missing link – that concerns the importance of incorporating insights from corporate governance (CG) literature when considering strategic HR decision-making.

Findings

A significant contribution of this paper to theory is to propose an integrative framework that conceptualises the elusive relationship between HRM and firm performance, and which draws on different literatures and multiple theoretical perspectives in to offer more holistic insights into the relationship. The paper discusses the implications of the integrative perspective for theory and practice.

Originality value

This paper argues that one of the main stumbling blocks for developing a better understanding of the mechanisms through which HRM creates value in an organisation is the fragmentation of the HRM literature between “HR as practices” and “HR as the department/profession”, as well as a tendency to neglect insights from the CG literature.
Trustee board diversity, governance mechanisms, capital structure and performance in UK charities
Authors: Elmagrhi Mohamed H. , Ntim Collins G. , Malagila John , Fosu Samuel , Tunyi Abongeh A.
Published: February 2018

Purpose

This paper aims to investigate the association among trustee board diversity (TBD), corporate governance (CG), capital structure (CS) and financial performance (FP) by using a sample of UK charities. Specifically, the authors investigate the effect of TBD on CS and ascertain whether CG quality moderates the TBD–CS nexus. Additionally, the authors examine the impact of CS on FP and ascertain whether the CS–FP nexus is moderated by TBD and CG quality.

Design/methodology/approach

The authors use a number of multivariate regression techniques, including ordinary least squares, fixed-effects, lagged-effects and two-stage least squares, to rigorously analyse the data and test the hypotheses.

Findings

First, the authors find that trustee board gender diversity has a negative effect on CS, but this relationship holds only up to the point of having three women trustees. The authors find similar, but relatively weak, results for the presence of black, Asian and minority ethnic (BAME) trustees. Second, the authors find that the TBD–CS nexus depends on the quality of CG, with the relationship being stronger in charities with higher frequency of meetings, independent CG committee and larger trustee and audit firm size. Third, the authors find that CS structure has a positive effect on FP, but this is moderated by TBD and CG quality. The evidence is robust to different econometric models that adjust for alternative measures and endogeneities. The authors interpret the findings within explanations of a theoretical perspective that captures insights from different CG and CS theories.

Originality/value

Existing studies that explore TBD, CG, CS and FP in charities are rare. This study distinctively attempts to address this empirical lacuna within the extant literature by providing four new insights with specific focus on UK charities. First, the authors provide new evidence on the relationship between TBD and CS. Second, the authors offer new evidence on the moderating effect of CG on the TBD-CS nexus. Third, the authors provide new evidence on the effect of CS on FP. Finally, the authors offer new evidence on the moderating effect of TBD and CG on the CS–FP nexus.
Leadership development strategy: the missing links
Authors: Maheshwari Shilpa Kabra , Yadav Jaya
Published: February 2018

Purpose

Current volatile environments, business complexity, and leadership gaps are compelling organizations to deploy effective leadership development strategies. Fueled by competitive growth and people challenges, efforts continue to scale up but fail to create the desired leaders. This paper aims to address the missing links and calls for new ways of deploying leadership development strategy.

Design/methodology/approach

Qualitative data on experiential feedback have been collected from participants and stakeholders of leadership development programs in Indian organizations.

Findings

An integrated six-step approach to leadership development has been proposed for scholars and practitioners.

Practical implications

From the practitioner’s perspective, this study contributes to the field of leadership development by challenging the relevance of current approaches. It also adds to the scholarly literature on leadership development in the context of the organization and the individual.

Originality/value

Current studies in the area of leadership development in the Indian context are scarce.