bluuebunny/crossref_metadata_2025 huggingface dataset:
Finite three-dimensional surface waves in circular channels
Authors: Spielvogel Lester Q.
Published: December 2016

This paper is concerned with finite surface waves in incompressible fluid in circular channels or bowls. Fluid circulates through these channels and is contained in them by the action of an axial gravitational force. Under certain velocity conditions permanent waves of finite magnitude may be solutions to the differential equations of motion. These waves are related to the cnoidal and solitary waves of the infinite straight channel. Using stretching techniques on the nonlinear differential equations, we derive expressions for the wave shape, the critical velocity condition, and relations to waves in straight channels. The irrotational case is thoroughly treated and a short discussion of the rotational case is included. The fact that these waves deform continuously into those already derived for straight channels is also discussed. The most important result, however, is that stretching techniques have been shown to describe finite waves progressing in curved trajectories. While it is true that the trajectories are dictated by the curvature of the containing vessels, it is apparent that this technique may very well be useful in describing finite wave shape and trajectories for waves near beaches and breakwaters.
Buckling of stochastically imperfect columns on nonlinear elastic foundations
Authors: Amazigo John C.
Published: December 2016

Approximate asymptotic expressions are obtained for the buckling stresses and autocorrelation of the lateral displacement of infinitely long imperfect columns resting on nonlinear elastic foundations. The imperfections are assumed to be homogeneous Gaussian random functions with known autocorrelation. The formulas are discussed and compared with previous results obtained by means of truncated hierarchy and equivalent linearization techniques.
The influence of dynamical thermal expansion on the propagation of plane elastic-plastic stress waves
Authors: Raniecki B.
Published: December 2016

In this paper the implications of the classical heat conduction equation for the problem of the propagation of plane waves caused by mechanical impulse and sudden heating at the boundary of an elastic-plastic half-space are presented. It is shown that the effect of dynamical thermal expansion is to reduce the jump in the stress at waves of strong discontinuity. The stress and temperature fields dealt with here are assumed to be thermodynamically uncoupled.
Viscous flow along a corner: Numerical solution of the corner layer equations
Authors: Rubin Stanley G. , Grossman Bernard
Published: December 2016

Solutions for the viscous incompressible flow along a right-angle corner have been found by a method of successive iteration. The algebraic nature of the asymptotic flow field has been utilized to provide boundary conditions for the numerical analysis. One arbitrary constant appearing in the asymptotic series has been determined by the elimination of interior mass sources that appear as a result of any inaccuracy in the value of this constant, allowing additional mass to cross the outer boundary. The numerical solution shows a swirling flow in the corner but a closed vortical pattern is not established.
Axisymmetric bifurcation in an elastic-plastic cylinder under axial load and lateral hydrostatic pressure
Authors: Cheng S. Y. , Ariaratnam S. T. , Dubey R. N.
Published: December 2016

Conditions for initiation of necking and bulging of elastic and elastic-plastic cylindrical solids are derived. The possibility of bifurcation of rigid-plastic solids and the conditions for homogeneous deformation with homogeneous stress are also investigated.
Instability of symmetric structural systems with independent loading parameters
Authors: Huseyin Koncay
Published: December 2016

The general post-critical characteristics of a discrete structural system with independent loading parameters are studied. Attention is restricted to elastic conservative systems which satisfy certain analytical symmetry conditions and which lose their initial stability at a ’symmetric special’ critical point. The results are compared with Koiter’s ’stable symmetric’ and ’unstable symmetric’ bifurcation points, and three theorems are established.
Radiation interaction between two solid half-spaces
Authors: Kleinstein G.
Published: December 2016

A solution to the radiation interaction problem between two solid half-spaces is obtained. A Green’s function method reduces the problem to the solution of two nonlinear integral equations for the surface temperatures which are solved by utilizing analytical and numerical techniques.
Elastic analysis of an axisymmetric stress field perturbed by a spheroidal inhomogeneity
Authors: Chen W. T.
Published: December 2016

An infinite elastic medium contains an elastic spheroidal inclusion. Both materials are transversely isotropic. Assuming that the stress field in the absence of any inhomogeneity is prescribed, it is desired to calculate the modification caused by the inclusion. This paper presents a general solution to this elasticity problem with the restriction that the prescribed stress field is axisymmetric. The analysis is based upon some new identities in Legendre functions, which are derived in this paper. The solution is in the form of combinations of Legendre functions. An example of a spheroidal cavity in a tension field is given.
A note on elastic-plastic flow
Authors: Danyluk H. T. , Pounder J. R. , Haddow J. B.
Published: December 2016

The plane plastic flow of an incompressible elastic perfectly-plastic solid that obeys the Mises yield condition and a properly invariant form of the Prandtl-Reuss equations is considered. It is shown that both the stress and velocity equations are hyperbolic and that the two families of characteristics are not coincident except for the limiting case of the rigid perfectly-plastic solid.
On the motion past thin airfoils of incompressible fluids with conductivity tensor
Authors: Dragos L.
Published: December 2016

This note is a study of the problem of the steady motion of an inviscid incompressible fluid past thin airfoils, the Hall effect being taken into account. The case of crossed fields (one of the most important in aerodynamics) is studied in detail. The results for the cases of aligned fields and Alfvén motion are also given. The general solution is represented by a continuous superposition of plane waves. The boundary conditions determine the solution by means of a Fredholm-type integral equation which may be solved with the aid of the method of successive approximations. If the parameter of the magneto-hydrodynamic interaction

(
S
)

\left ( S \right )

is equal to zero, one obtains the known solution of classical aerodynamics. The equation is solved explicitly for Alfvén motion.
Continuum thermodynamics with surfaces: Restrictions on constitutive equations
Authors: Fisher George M. C. , Leitman Marshall J.
Published: December 2016

In an earlier paper we deduced, using measure theoretic concepts, forms for the first and second laws of thermodynamics on surfaces which are distinguished by area-continuous and time-dependent energy and entropy. In that paper we avoided making constitutive assumptions since we sought expressions for the physical laws which were, indeed, independent of particular material assumptions.
A variational approach to statistically nonhomogeneous fields
Authors: Somoroff A.
Published: December 2016

Classical variational principles of elasticity are cast in a form amenable to the treatment of certain problems concerned with statistically nonhomogeneous fields. The variational principles are utilized to obtain bounds directly upon the ensemble average values of physical quantities which in some sense characterize their problems. General formulations and applications are given for randomly heterogeneous elastic media and elastically supported beams with random axial variation of sectional rigidity and foundation stiffness. Bounds are obtained for the average displacement at the inner surface of a hollow sphere under pressure, the average elongation of a cylinder in uniform tension, and the average displacement of a beam directly under a point load. General methods are given for the selection of the deterministic admissible functions which provide the best bounds that can be obtained from classical principles for this restricted class of admissible functions. The closeness of the bounds is of the same order as the elementary bounds on effective material properties, which are of quantitative value only for small dispersion of the random coefficients. In a special statistically homogeneous case, previously obtained bounds for an effective Young’s modulus are regained. Usually, however, the bounded quantities do not possess the generality of effective properties but are more closely associated with the results of particular problems. The developments of the present paper are considered an initial approach to the investigation of statistically nonhomogeneous problems.
The general problem of long waves on a rotating earth
Authors: Chambers LL. G.
Published: December 2016

A method is given which makes it possible to calculate the surface elevation associated with long waves on a rotating earth when fluid is created or passes over geometrical boundaries.
On linearized theory for compressible viscous planar flow with slip
Authors: Fendell F. E.
Published: December 2016

Steady compressible supersonic planar flow of a viscous heat-conducting fluid is examined under linearization about freestream conditions. Although the results are derived here for a large-Prandtl-number fluid, Wu has shown that the conclusions hold for an order-unity-Prandtl-number fluid in the limits of large and small Reynolds numbers. First the compressible correction to the fundamental solution for flow past a singular flat plate (a point source of momentum directed antiparallel to the uniform freestreaming) is examined. Results valid near the point source are obtained by contour integration. Then these results are superposed to form an integral equation describing linearized slip flow past a finite flat plate at zero angle of attack. The large-slip limit for a short plate is characterized as a regular perturbation limit while the small-slip limit has singular-perturbation characteristics. For a long flat plate the integral equation can be approximated as Poisson type and is easily solved; for a short flat plate the integral equation can be approximated as a Carleman equation of the second kind and is less readily solved. However, an approximate solution for the shear near the leading edge of a short flat plate with small slip is given through the Wiener-Hopf technique. The integral equation describing thermal slip at a finite flat plate is seen to be like that describing velocity slip.
The diffraction of a plane compressional elastic wave by a rigid circular disc
Authors: Datta S. K.
Published: December 2016

The paper deals with the low-frequency diffraction of a plane compressional elastic wave incident obliquely on a rigid circular disc embedded in an infinite elastic medium. The motion of the disc, both rotational and translational, has been discussed in detail. By letting the mass of the disc go to infinity one obtains the results for diffraction by a fixed disc. Far-field amplitude of the scattered field has also been obtained. This can be used to calculate the scattering cross-section of the disc. It is found that for long wavelengths the scattering coefficient varies as the fourth power of the wave number if the disc is movable, whereas it is independent of the wave number if the disc is fixed.
Eigenfunctions corresponding to the band pass kernel with large center frequency
Authors: Jerri A. J.
Published: December 2016

It is known that the eigenfunctions of the finite integral equation with band limited difference kernel are the prolate spheroidal wave functions. When the band pass difference kernel was considered, no such well-known functions were found, except for the limiting case of zero band width. In this report we show that for large values of the center frequency the eigenfunctions corresponding to the band pass kernel are related to the prolate spheroidal functions.
Asymptotics for a system of nonlinearly coupled wave equations with an application to the galloping oscillations of overhead transmission lines
Authors: van Horssen W. T.
Published: December 2016

In this paper an asymptotic theory for a class of initial-boundary value problems for systems of weakly and nonlinearly coupled wave equations is presented. The theory implies the well-posedness of the problem in the classical sense and the asymptotic validity of formal approximations on long time scales.
Singular asymptotics analysis for the singularity at a hole near a boundary
Authors: Callias Constantine J. , Markenscoff Xanthippi
Published: December 2016

The hoop stress at a hole near the edge of a plate loaded in tension is analyzed as the hole approaches the boundary. The solution given by Mindlin in terms of a series is converted to an integral to which singular asymptotics are applied to obtain the singularity in the limit.
An asymptotic stability condition for inhomogeneous simple shear
Authors: Chen H. Tz. , Douglas A. S. , Malek-Madani R.
Published: December 2016

Analytic steady solutions of inhomogeneous simple shear with isothermal and stress boundary conditions are found. The material is assumed to be thermoviscous and inertia and heat conduction effects are included. The basic inhomogeneous solution is spatially dependent, but time independent. Bifurcation of this solution, as the parameters vary, is analyzed. It is shown that there is a critical value of the parameter, corresponding to thermal softening, below which two steady state solutions exist for specified values of other parameters. A linear perturbation method, which gives rise to a linear set of partial differential equations (with spatially dependent coefficients), is used to distinguish the stable branch of the bifurcation diagram. After separation of variables, the existence of eigenvalues and eigenfunctions of the resulting fourth-order system is demonstrated. An asymptotic solution to the eigenvalue problem, for the case when an appropriate parameter is set equal to zero, is obtained explicitly. An integral method is then used in the general case to obtain a sufficient condition for stability.
Analytical representation of integrals relevant to coherent imaging
Authors: Pimbley J. M. , Silverstein S. D.
Published: December 2016

This work presents and evaluates three classes of definite integrals which can arise in the signal processing analysis of coherent imaging systems. All integrals yield to the method of contour integration in the complex plane. Such a treatment requires physically reasonable constraints on the beam divergence, apodizing function of the phased array. The physical foundation of the three integral classes is described in the text.
The initial value problem for acoustic gravity waves
Authors: McCartor Gary
Published: December 2016

The initial value problem for acoustic-gravity waves in atmospheres composed of one or two isothermal layers is solved. For the case of two layers the problem is formulated in an indefinite space.
The roots of 𝐽₀(𝑧)-𝑖𝐽₁(𝑧)=0
Authors: Macdonald D. A.
Published: December 2016

Synolakis [1] has proved that the equation
\[

J
0

(
z
)

−
i

J
1

(
z
)

=
0

{J_0}\left ( z \right ) - i{J_1}\left ( z \right ) = 0

\]
has no zeros in the half plane Im

z
>
0

z > 0

. In this note a table of the first thirty roots, correct to

O

(

10

−
6

)

O\left ( {{{10}^{ - 6}}} \right )

, is presented and an asymptotic formula, which is correct to better than one tenth of one percent for the smallest zero, is derived.
Heat flux density distribution on the electrodes of an arc
Authors: Bish R. L.
Published: December 2016

A general formula is derived for the radiant heat flux density on the surfaces of the electrodes of an electric arc. The formula is applied to a vertical arc burning above a cone-shaped electrode. In the case of a

90
∘

{90^ \circ }

cone, or flat plate, the heat flux density distribution shares the same general form as the Gaussian distribution. It is shown that the effect of decreasing the cone angle is to increase the flux density at the cone vertex and to diminish this flux elsewhere on the cone surface.
Bifurcation in elastic-plastic solids in plane stress
Authors: Dubey R. N. , Ariaratnam S. T.
Published: December 2016

A sufficient condition for bifurcation of equilibrium for an elastic-plastic solid under a state of plane stress is established. The bifurcation is found to occur in any of the following modes: (i) symmetric mode corresponding to necking or bulging, (ii) antisymmetric mode corresponding to buckling and (iii) mode of deformation localized at the surface.
On stability of the flow of a stratified gas over a liquid
Authors: Sontowski John F. , Seidel Barry S. , Ames William F.
Published: December 2016

Instabilities of the superposed flow of a gas over a liquid are considered under the assumption of inviscid, incompressible flow. The effects of density stratification in the gas are examined, and in so doing, two separate and different types of instabilities are revealed. As the velocity of the gas relative to the liquid increases from zero, there first appears an instability of a selective and relatively weak nature referred to as the initial instability. This is followed, at higher velocities, by a stronger type of instability called the gross instability. The initial instability takes the form of two distinct waves of different lengths, one superimposed upon the other. This superposition of two waves at low velocity is in accord with experimental observations, as are the calculated critical velocity and wavelength at which they first occur. The gross instability, on the other hand, is composed of a continuous spectrum of unstable waves, and is simply a slight refinement of the classical result of Kelvin. Such an occurence of two separate instabilities is in agreement with Munk’s experimentally based contention that Kelvin’s solution is not incorrect, as originally believed, but rather represents an actual instability which, however, is preceded by an additional and different type of instability.
Wave propagation in an elastic solid with a line of discontinuity or finite crack
Authors: Sih G. C. , Loeber J. F.
Published: December 2016

With the aid of integral transforms, a method is presented for solving the problem of scattering of plane harmonic compression and shear waves by a line of discontinuity or crack of finite width embedded in an elastic medium of infinite extent. When the incoming waves are applied in an arbitrary direction, the scattered-wave field may be determined by separating the crack-surface boundary conditions into functions even and odd with respect to the variable along the line crack. The problem is reduced to the evaluation of a system of coupled Fredholm integral equations with special emphasis placed on finding the near-field solution which consists of a knowledge of the detailed structure of the displacements and stresses in a small region around the crack vertex. Dynamic stress-intensity factors, the critical values of which govern the condition of crack propagation, are defined and found to be dependent on the incident wave length and Poisson’s ratio of the medium. At certain wave lengths, they are larger than those encountered under static loading. Such information is of particular importance in perdicting the fracture strength of structures subjected to oscillating loads.
Two-dimensional pulse propagation in a two-parameter anisotropic elastic solid
Authors: Payton Robert G.
Published: December 2016

A perturbing body force, in the form of an impulsive point source, is suddenly introduced into an anisotropic elastic body. The anisotropic solid is characterized by two parameters. After placing suitable restrictions on these parameters, integral representations of the transient displacement components are found. Explicit expressions for the displacements are obtained along two perpendicular lines which are centered at the point of application of the point impulse and parallel to the coordinate axes. Wave front singularities are identified and graphical results for the wave shapes are presented.
bnstruct: an R package for Bayesian Network structure learning in the presence of missing data
Authors: Franzin Alberto , Sambo Francesco , Di Camillo Barbara
Published: December 2016

Motivation

A Bayesian Network is a probabilistic graphical model that encodes probabilistic dependencies between a set of random variables. We introduce bnstruct, an open source R package to (i) learn the structure and the parameters of a Bayesian Network from data in the presence of missing values and (ii) perform reasoning and inference on the learned Bayesian Networks. To the best of our knowledge, there is no other open source software that provides methods for all of these tasks, particularly the manipulation of missing data, which is a common situation in practice.

Availability and Implementation

The software is implemented in R and C and is available on CRAN under a GPL licence.

Supplementary information

Supplementary data are available at Bioinformatics online.
T-BAS: Tree-Based Alignment Selector toolkit for phylogenetic-based placement, alignment downloads and metadata visualization: an example with the Pezizomycotina tree of life
Authors: Carbone Ignazio , White James B , Miadlikowska Jolanta , Arnold A Elizabeth , Miller Mark A , Kauff Frank , U'Ren Jana M , May Georgiana , Lutzoni François
Published: December 2016

Motivation

High-quality phylogenetic placement of sequence data has the potential to greatly accelerate studies of the diversity, systematics, ecology and functional biology of diverse groups. We developed the Tree-Based Alignment Selector (T-BAS) toolkit to allow evolutionary placement and visualization of diverse DNA sequences representing unknown taxa within a robust phylogenetic context, and to permit the downloading of highly curated, single- and multi-locus alignments for specific clades.

Results

In its initial form, T-BAS v1.0 uses a core phylogeny of 979 taxa (including 23 outgroup taxa, as well as 61 orders, 175 families and 496 genera) representing all 13 classes of largest subphylum of Fungi—Pezizomycotina (Ascomycota)—based on sequence alignments for six loci (nr5.8S, nrLSU, nrSSU, mtSSU, RPB1, RPB2). T-BAS v1.0 has three main uses: (i) Users may download alignments and voucher tables for members of the Pezizomycotina directly from the reference tree, facilitating systematics studies of focal clades. (ii) Users may upload sequence files with reads representing unknown taxa and place these on the phylogeny using either BLAST or phylogeny-based approaches, and then use the displayed tree to select reference taxa to include when downloading alignments. The placement of unknowns can be performed for large numbers of Sanger sequences obtained from fungal cultures and for alignable, short reads of environmental amplicons. (iii) User-customizable metadata can be visualized on the tree.

Availability and Implementation

T-BAS Version 1.0 is available online at http://tbas.hpc.ncsu.edu. Registration is required to access the CIPRES Science Gateway and NSF XSEDE's large computational resources.

Supplementary information

Supplementary data are available at Bioinformatics online.
Mycobacterium indicus pranii (Mw)-mediated protection against visceral leishmaniasis by reciprocal regulation of host dual-specificity phosphatases
Authors: Parveen Shabina , Bandhyopadhyay Syamdas , Das Sonali , Majumdar Suchandra Bhattacharyya , Jawed Junaid Jibran , Chowdhury Bidisha Paul , Saha Bhaskar , Majumdar Subrata
Published: December 2016

Leishmania donovani resides within the host macrophages by dampening host defence mechanisms and thereby it modulates the host cell functions for its survival. Multiple host cell factors compete during the interplay between the host and the parasite. Roles for dual-specificity phosphatases (DUSPs) are implicated in various pathological conditions. However, the reciprocity of these DUSPs was unknown in L. donovani infection in a susceptible model. Here, we show that Mycobacterium indicus pranii (Mw), an immunomodulator, reciprocally regulates DUSP1 and DUSP6 through the TLR4 pathway. Association of PKC-β with DUSP6 increases after Mw treatment resulting in decreased IL-10, phosphorylation of ERK1/2 and Arginase-1, whereas Mw treatment decreases the association between PKC-ε and DUSP1 resulting in increased IL-12, phosphorylation of p38 and inducible nitric oxide synthase expression. Silencing of DUSP1 or over-expression of DUSP6 in L. donovani-infected BALB/c mice decreases the parasite burden by inducing IL-12 and reducing IL-10 production. Therefore, we identify DUSP1 and DUSP6 as therapeutic targets, functions of which could be favourably modulated by Mw during L. donovani infection.
Harms to “Others” and the Selection Against Disability View
Authors: Williams Nicola Jane
Published: December 2016

In recent years, the question of whether prospective parents might have a moral obligation to select against disability in their offspring has piqued the attention of many prominent philosophers and bioethicists, and a large literature has emerged surrounding this question. Rather than looking to the most common arguments given in support of a positive response to the abovementioned question, such as those focusing on the harms disability may impose on the child created, duties and role-specific obligations, and impersonal ‘harms’, a less commonly made set of arguments is focused upon which looks to the harms that a decision not to select against disability may impose on others. Three different possible arguments supporting a limited duty of disability avoidance are thus identified and subsequently explored: harms to parents themselves, harms to existing family members, and harms to other existing members of society.
Association of Sociodemographic Factors with Spirituality and Hope in Patients with Diabetic Foot Ulcers
Authors: Salomé Geraldo Magela , de Almeida Sergio Aguinaldo , Mendes Bruno , de Carvalho Maiume Roana Ferreira , Bueno José Carlos , Massahud Marcelo Renato , Ferreira Lydia Masako
Published: December 2016

OBJECTIVE:

To evaluate levels of spirituality and hope in patients with diabetic foot ulcers (DFUs) according to sociodemographic factors.

DESIGN:

This was a primary, prospective, descriptive, analytical, and clinical study. Questionnaires assessing sociodemographic and clinical characteristics of the patients, the Spirituality Self-rating Scale (SSRS), and the Herth Hope Index (HHI) were administered to all participants.

SETTING:

University-affiliated skilled nursing center and outpatient wound care clinic in Pouso Alegre, Brazil.

PATIENTS:

Fifty adult patients with DFUs participated in the study. Patients with ischemic diabetic foot and mixed ulcers were excluded from the study.

MAIN RESULTS:

On average, patients with DFUs had low levels of spirituality (mean SSRS score, 12.6) and low hope for cure (mean HHI, 16.5). Patients younger than 60 years reported significantly lower levels of spirituality (mean SSRS scores, 11.0), and those older than 70 years had significantly lower hope for cure (mean HHI, 12.5) than other age groups (P = .040). Level of spirituality was significantly lower among women (P = .015) and those living with an ulcer for more than 2 years, who also reported significantly lower hope for cure (P = .029) compared with patients having an ulcer for less than 2 years.

CONCLUSION:

On average, patients with DFUs, especially women and older adults, had a low sense of hope and spirituality. Except for gender, age, and ulcer duration, other sociodemographic and ulcer characteristics had no significant effect on the study population’s spirituality and hope.
Older Adults, Falls, and Skin Integrity
Authors: Cheung Catherine
Published: December 2016

GENERAL PURPOSE:

To provide an overview of the assessment and management of risk factors for falls in older adults.

TARGET AUDIENCE:

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant should be better able to:

1. Outline the components of an evidence-based falls assessment and identify risk factors for falls.

2. Specify strategies to reduce falls in older adults, especially as related to maintaining skin integrity.

Older adult patients may present to skin and wound care clinicians with skin injuries as a result of falls. In addition, chronic wounds associated with the patient’s conditions may also increase his/her falls risk. Hence, appropriate assessment and management of the risk of falls in older adult patients are key elements of patient-centered care.
Neoadjuvant Chemotherapy for Newly Diagnosed, Advanced Ovarian Cancer: Society of Gynecologic Oncology and American Society of Clinical Oncology Clinical Practice Guideline
Authors: Wright Alexi A. , Bohlke Kari , Armstrong Deborah K. , Bookman Michael A. , Cliby William A. , Coleman Robert L. , Dizon Don S. , Kash Joseph J. , Meyer Larissa A. , Moore Kathleen N. , Olawaiye Alexander B. , Oldham Jessica , Salani Ritu , Sparacio Dee , Tew William P. , Vergote Ignace , Edelson Mitchell I.
Published: December 2016

(Abstracted from J Clin Oncol 2016;34:3460–3473)

Treatment with primary cytoreductive surgery (PCS) followed by neoadjuvant chemotherapy (NACT) has been the standard of care for women with stage IIIC or IV epithelial ovarian cancer (EOC). However, data from 2 recent randomized controlled trials suggest that PCS can be a first option in these women.
Closed-Loop Insulin Delivery During Pregnancy in Women With Type 1 Diabetes
Authors: Stewart Zoe A. , Wilinska Malgorzata E. , Hartnell Sara , Temple Rosemary C. , Rayman Gerry , Stanley Katharine P. , Simmons David , Law Graham R. , Scott Eleanor M. , Hovorka Roman , Murphy Helen R.
Published: December 2016

(Abstracted from N Engl J Med 2016;375:644–654)

In women with diabetes mellitus (DM) and pregnancy, congenital anomalies have been shown to be associated with poor glycemic control around the time of conception. In addition, other complications are associated with maternal hyperglycemia throughout pregnancy.
Ketamine Increases the Function of γ-Aminobutyric Acid Type A Receptors in Hippocampal and Cortical Neurons
Authors: Wang Dian-Shi , Penna Antonello , Orser Beverley A.
Published: December 2016

Background

The “dissociative ” general anesthetic ketamine is a well-known N-methyl-d-aspartate receptor antagonist. However, whether ketamine, at clinically relevant concentrations, increases the activity of inhibitory γ-aminobutyric acid (GABA) receptor type A (GABAA) receptors in different brain regions remains controversial. Here, the authors studied the effects of ketamine on synaptic and extrasynaptic GABAA receptors in hippocampal neurons. Ketamine modulation of extrasynaptic GABAA receptors in cortical neurons was also examined.

Methods

Whole cell currents were recorded from cultured murine neurons. Current evoked by exogenous GABA, miniature inhibitory postsynaptic currents, and currents directly activated by ketamine were studied.

Results

Ketamine did not alter the amplitude, frequency, or kinetics of postsynaptic currents but increased a tonic inhibitory current generated by extrasynaptic GABAA receptors in hippocampal neurons. For example, ketamine (100 µM) increased the tonic current by 33.6 ± 6.5% (mean ± SEM; 95% CI, 18.2 to 48.9; n = 8, P < 0.001). Ketamine shifted the GABA concentration–response curve to the left, but only when GABAA receptors were activated by low concentrations of GABA (n = 6). The selective increase in tonic current was attributed to ketamine increasing the apparent potency of GABA at high-affinity extrasynaptic GABAA receptors. Ketamine also increased a tonic current in cortical neurons (n = 11). Ketamine directly gated the opening of GABAA receptors, but only at high concentrations that are unlikely to occur during clinical use.

Conclusions

Clinically relevant concentrations of ketamine increased the activity of high-affinity extrasynaptic GABAA receptors in the hippocampus and cortex, an effect that likely contributes to ketamine’s neurodepressive properties.
Association of Ipsilateral Rib Fractures With Displacement of Midshaft Clavicle Fractures
Authors: Stahl Daniel , Ellington Matthew , Brennan Kindyle , Brennan Michael
Published: December 2016

Objectives:

To determine whether the presence of ipsilateral rib fractures affects the rate of a clavicle fracture being unstable (>100% displacement).

Design:

A retrospective review from 2002–2013 performed at a single level 1 trauma center evaluated 243 midshaft clavicle fractures.

Setting:

Single Level 1 trauma center.

Patients/Participants:

These fractures were subdivided into those with ipsilateral rib fractures (CIR; n = 149) and those without ipsilateral rib fractures (CnIR; n = 94).

Intervention:

The amount of displacement was measured on the initial injury radiograph and subsequent follow-up radiographs.

Main Outcome Measurements:

Fractures were classified into either <100% displacement or >100% displacement, based on anteroposterior radiographs. Ipsilateral rib fractures were recorded based on which number rib was fractured and the total number of fractured ribs.

Results:

One hundred sixteen (78%) of the CIR group and 51 (54%) of the CnIR group were found to have >100% displacement at follow-up (P = 0.0047). Seventy-two percent of the CIR group demonstrated progression from <100% to >100% displacement of the fracture compared with only 54% of the CnIR group (P < 0.05). The odds ratio for progression of the clavicle fracture to >100% was 4.08 (P = 0.000194) when ribs 1–4 were fractured and not significant for rib fractures 5–8 or 9–12.

Conclusions:

The presence of concomitant ipsilateral rib fractures significantly increases the rate of midshaft clavicle fractures being >100% displaced. In addition, a fracture involving the upper one-third of the ribs significantly increases the rate of the clavicle fracture being >100% displaced on early follow-up. Clavicle fractures with associated ipsilateral rib fractures tend to demonstrate an increased amount of displacement on follow-up radiographs compared with those without ipsilateral rib fractures.

Level of Evidence:

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
Balloon Cell Melanoma and Its Metastasis, a Rare Entity
Authors: Chavez-Alvarez Sonia , Villarreal-Martinez Alejandra , Miranda-Maldonado Ivett , Ocampo-Candiani Jorge , Garza-Rodriguez Veronica
Published: December 2016

Balloon cell melanoma (BCM) with metastasis is a rarely occurring neoplasia. The incidence of BCM is low, and hence, the frequency of these lesions presenting metastasis is even less frequent. This review exposes the balloon cell metastasis cases that have been published and a new case. These cases share the histopathological features but the location of initial melanoma, age and sex vary. It is relevant for the dermatologist and dermatopathologist to keep in mind the diagnosis of BCM and consider the possibility of it metastasizing as nonpigmented skin lesions.
Reduction of Myocardial Ischemia–Reperfusion Injury by Inhibiting Interleukin-1 Alpha
Authors: Mauro Adolfo G. , Mezzaroma Eleonora , Torrado Juan , Kundur Priyanka , Joshi Priyashma , Stroud Kelsey , Quaini Federico , Lagrasta Costanza A. , Abbate Antonio , Toldo Stefano
Published: December 2016

Background:

Interleukin-1α (IL-1α) released by dying cells is an alarmin that activates the innate immunity. We hypothesized that after myocardial ischemia–reperfusion (I/R) injury, IL-1α amplifies the myocardial damage by activating the inflammasome and caspase-1.

Methods:

Adult male CD1 mice were used. The left anterior descending coronary artery was ligated for 30 minutes, after 24 hours of reperfusion. An IL-1α blocking antibody (15 μg/kg intraperitoneally) or matching vehicle was given after reperfusion. A subgroup of mice underwent sham surgery. We assessed the effects of IL-1α blockade on caspase-1 activity, infarct size, cardiac troponin I serum levels, and left ventricular fractional shortening, 24 hours after I/R.

Results:

I/R led to inflammasome formation, and IL-1α blockade significantly reduced inflammasome formation, reflected by a >50% reduction in caspase-1 activity versus vehicle (P = 0.03). IL-1α blockade also reduced the infarct size (−52% infarct expressed as percentage of area at risk, and −79% for cardiac troponin I serum levels, P < 0.001 vs. vehicle) and preserved the left ventricular fractional shortening (31 ± 3% vs. 25 ± 2%, P < 0.001 vs. vehicle).

Conclusion:

IL-1α blockade after I/R reduces the inflammasome activation, decreases the infarct size, and preserves the left ventricular function. IL-1α blockade may therefore represent a novel therapeutic strategy to reduce I/R injury.
Treatment of Radial Nonunion with Corticocancellous Bone Graft and Fascia of Anterolateral Thigh Free Flap: The Wrap Technique
Authors: Cherubino Mario , Ronga Mario , Sallam Davide , Fagetti Alessandro , Valdatta Luigi , Cherubino Paolo
Published: December 2016

The management of nonunion of the forearm bones is a challenging task. Multiple factors have been associated with the establishment of forearm nonunion, such as the fracture position and complexity, general condition of the patient, and the previously utilized surgical technique. The optimal surgical treatment of a bone gap remains a subject of discussion. Autogenous corticocancellous bone grafts and vascularized bone flaps have been used with differing results. The authors describe a technique for the treatment of posttraumatic nonunion of the radius with a 5-cm bone gap using the free anterolateral thigh fascial flap wrapped around a tricortical iliac bone graft. The fracture healed after 5 weeks. The use of a vascularized tissue wrapped around the bone graft resulted in a well-healed bone and no signs of resorption after 2 years of follow-up. A bone graft wrapped by a fascial flap could magnify the restorative effect on the bone defect because of its dual role of constructing vascularization and inducing tissue regeneration.
GORE-TEX VASCULAR GRAFT FOR MACULAR BUCKLING IN HIGH MYOPIA EYES
Authors: Wu Pei-Chang , Sheu Jiunn-Jye , Chen Yi-Hao , Chen Yung-Jen , Chen Chih-Hsin , Lee Jong-Jer , Huang Chih-Ling , Chen Chueh-tan , Kuo Hsi-Kung
Published: December 2016

Purpose:

To evaluate a new application of an expanded polytetrafluoroethylene (Gore-Tex) vascular graft for use in macular buckling surgery for treatment of highly myopic eyes.

Methods:

The Gore-Tex vascular graft was used as a macular buckling material in eight consecutive cases of myopic macular diseases which included fovea detachment, foveoschisis, or macular hole retinal detachment.

Results:

Retinal reattachment was achieved in all cases except one which had partial resolution (88%). The postoperative best-corrected visual acuity ranged from 20/2000 to 20/100 depending on the degree preexisting macular degeneration, and significant better than the preoperative best-corrected visual acuity (P = 0.048, paired t-test). During the follow-up period, which ranged from 8 months to 3 years, no eye developed buckle-related complications such as infection or dislocation.

Conclusion:

The initial pilot results from this series using a Gore-Tex graft for macular buckling is promising. Throughout the follow-up period, the Gore-Tex was well tolerated in the highly myopic eyes. Large scale and long-term follow-up is warranted.
EN-FACE OPTICAL COHERENCE TOMOGRAPHY IMAGING IN A CASE OF CHOROIDAL RUPTURE
Authors: Mase Tomoko , Ishiko Satoshi , Tani Tomofumi , Yoshida Akitoshi
Published: December 2016

Purpose:

To report a case of choroidal rupture resulting due to blunt trauma using en-face optical coherence tomography (OCT) imaging.

Methods:

Case report.

Results:

A 22-year-old man sustained a blunt trauma to his right eye. At the initial examination, four lesions with a subretinal hemorrhage were observed during a fundus examination of the macular area including the fovea, but the findings under the lesions were unclear. The authors observed the extent of the minute findings noninvasively by en-face OCT imaging from the initial examination. Six months after the trauma, the fine crescent-shaped lines seen by angiography and OCT B-scan images were consistent with findings observed on the en-face OCT images.

Conclusion:

The en-face OCT imaging would be useful to examine the pathological changes in a choroidal rupture noninvasively during frequent follow-up examinations in a case of choroidal rupture.
Mid-Term Results of a Single Intrastromal Corneal Ring Segment for Mild to Moderate Progressive Keratoconus
Authors: Miraftab Mohammad , Hashemi Hassan , Hafezi Farhad , Asgari Soheila
Published: December 2016

Purpose:

To study the mid-term effects of implanting a single intracorneal ring segment (ICRS) for treatment of mild to moderate progressive keratoconus.

Methods:

This retrospective study was conducted on patients with progressive keratoconus treated with ICRS. The mean follow-up time was 15.2 ± 8.8 (range, 7–26) months before and 27.8 ± 7.5 (range, 18–35) months after surgery. Patients received no other treatment during this time. Of the cases studied, 59.1% had inferior keratoconus.

Results:

Thirty eyes of 30 patients with a mean age of 27.5 ± 4.6 years were included in the study. Corrected distance visual acuity decreased by 1 line during the preoperative follow-up and improved by 2 lines after surgery (P < 0.05). Maximum keratometry (Kmax) of the anterior (2.39 ± 0.75 D) and posterior (0.33 ± 0.32 D) corneas at 3 mm and anterior Kmax at 8 mm (2.39 ± 0.95 D) decreased after treatment (all P < 0.05). The posterior Q value shifted toward a more oblate curvature (0.50 ± 0.52, P = 0.023). Decreases in anterior elevation at the thinnest point (5.22 ± 7.21 μm) and posterior corneal central elevation (8.89 ± 11.26 μm) were significant (both P < 0.05). Corneal thickness at the center (11.11 ± 12.38 μm) and thinnest point (15.89 ± 12.75 μm) increased after treatment (all P < 0.001). Other significant changes included postoperative decreases in the keratoconus index (0.12 ± 0.06), index of height decentration (0.06 ± 0.05), index of surface variance (27.32 ± 13.08), index of vertical asymmetry (0.42 ± 0.21), index of height asymmetry (8.42 ± 20.57), and an increase in the center keratoconus index (0.01 ± 0.02) (P < 0.001).

Conclusions:

This study demonstrates that ICRS implantation provides favorable mid-term outcomes in treatment of mild and moderate progressive keratoconus and can improve corneal indices compared with their preoperative states.
Analysis of Factors Affecting the Outcomes of In-hospitalized Vestibular Rehabilitation in Patients With Intractable Dizziness
Authors: Goto Fumiyuki , Nomura Kyoko , Taka Fumiaki , Arai Miki , Sugaya Nagisa
Published: December 2016

Objective:

To analyze somatic and psychological factors affecting the outcomes of in-hospital vestibular rehabilitation in patients with intractable dizziness.

Materials and Methods:

The study involved 138 patients with persistent dizziness caused by peripheral vestibular dysfunction. They were hospitalized and taught to conduct a vestibular rehabilitation program for 30 minutes by themselves three times a day over 5 days. They were then instructed to continue performing the program every day after discharge. Several questionnaires were conducted immediately before, and 1 month after, the treatment. For example, the dizziness handicap inventory (DHI), the somatosensory catastrophizing scale (SSCS), and indexes of depression and anxiety. Posturography was also performed. The main outcome was the difference between the DHI scores before and after rehabilitation. Body sway was objectively evaluated using static posturography.

Results:

The vestibular rehabilitation significantly improved the DHI score, the SSCS score, depression, and anxiety. Multivariate analysis indicated that the improvement in the DHI score was poorer in patients who showed high SSCS score before intervention. A higher prevalue of the DHI was associated with greater improvements in this perceived handicap after the rehabilitation. Small body sway pre-rehabilitation was related to positive effects on the DHI score in patients with a high prevalue of the DHI.

Conclusion:

The vestibular rehabilitation contributed to the improvement of perceived handicap due to dizziness, catastrophization of bodily sensation, and emotional distress. Patients who catastrophized their bodily sensations before vestibular rehabilitation saw smaller improvements in perceived handicap due to dizziness.
The Resilience in Illness Model Part 2: Confirmatory Evaluation in Adolescents and Young Adults With Cancer
Authors: Haase Joan E. , Kintner Eileen K. , Robb Sheri L. , Stump Timothy E. , Monahan Patrick O. , Phillips Celeste , Stegenga Kristin A. , Burns Debra S.
Published: December 2016

Background:

Empirically derived and tested models are necessary to develop effective, holistic interventions to improve positive health outcomes in adolescents and young adults (AYA) with cancer, yet few exist. This article is the second of 2 articles reporting on evaluation of the Resilience in Illness Model (RIM) as a predictive model to guide positive health research and practice.

Objective:

The aim of this study was to report the confirmatory model evaluation of the RIM.

Methods:

A confirmatory evaluation of RIM was done using baseline data from a sample of 113 AYA aged 11 to 24 years who were undergoing hematopoietic stem cell transplant and enrolled in a randomized controlled trial of a behavioral intervention to enhance resilience. Data were analyzed using latent variable structural equation modeling.

Results:

Goodness-of-fit indices supported RIM as a confirmed model that accounted for large amounts of variance in the outcomes of self-transcendence (62%) and resilience (72%), and in 3 of 5 mediators, specifically social integration (74%), courageous coping (80%), and hope-derived meaning (87%), as well as small to moderate amounts of variance in the remaining mediators of defensive coping (1%) and family environment (35%).

Conclusions:

Findings establish the RIM as a plausible predictive framework for explaining ways AYA with cancer transcend their illness and achieve resilience resolution and for guiding intervention studies in this population. Additional research is needed to explore RIM’s transferability based on stage of illness, other chronic diseases, and cultural diversity.

Implications for Practice:

Results support the RIM as an appropriate guide for developing and evaluating interventions to foster positive adjustment in AYA with cancer.
Caesarean Section Rates and Adverse Neonatal Outcomes After Induction of Labour Versus Expectant Management in Women With an Unripe Cervix: A Secondary Analysis of the HYPITAT and DIGITAT Trials
Authors: Bernardes T. P. , Broekhuijsen K. , Koopmans C. M. , Boers K. E. , van Wyk L. , Tajik P. , van Pampus M. G. , Scherjon S. A. , Mol B. W. , Franssen M. T. , van den Berg P. P. , Groen H.
Published: December 2016

(Abstracted from BJOG 2016;123:1501–1508)

Between 20% and 25% of pregnancies require induction of labor (IOL), especially in situations that indicate better outcomes for mother and child if the pregnancy is not further prolonged. However, the effectiveness of IOL is subject to considerable debate because of concerns regarding the associated high rates of cesarean deliveries in women with an unripe cervix.