bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of real‐time lung tumor motion monitoring using intrafractional ultrasound and kV cone beam projection images
Authors: Mostafaei Farshad , Tai An , Gore Elizabeth , Johnstone Candice , Haase William , Ehlers Christopher , Cooper David T. , Lachaine Martin , Li X. Allen
Published: July 2018

Purpose

The ability to monitor intrafractional tumor motion is essential for radiation therapy of thoracic and abdominal tumors. This study aims to develop a method to track lung tumor motion using intrafractional continuous ultrasound (US) and periodic cone‐beam projection images (CBPI).

Methods

Time‐sequenced b‐mode US and CBPI data were extracted from the data acquired with the Clarity® and XVI platforms on an Elekta linac, respectively. The data were synchronized through a video capture card (VCE‐PRO, IMPERX Inc.) which was triggered by the XVI system. In this way, a system was configured to allow real‐time acquisition of the diaphragm position synchronized with periodic acquisition of the lung tumor position. Feasibility of the system was demonstrated by acquiring synchronized data on an in‐house motion platform with embedded spheres of different materials and US images of the diaphragm on 5 volunteers of various body sizes. Finally, ultrasound b‐mode images and CBPI were also acquired simultaneously from 3 lung cancer patients.

Results

Diaphragm motion monitoring under free breathing (FB) was successful with intracostal US imaging. We observed that diaphragm visualization decreased with the increase in the body size of the volunteer. The US system was able to track the motion as small as 2 mm in the phantom. The intrafractional CBPI acquired during VMAT delivery was successfully synchronized with US acquisition in a phantom study. Collected patient data showed a significant correlation between diaphragm motion, an internal surrogate monitored by US, and the tumor motion in superior–inferior (SI) direction monitored by XVI (P ˂ 0.0001).

Conclusions

The feasibility of real‐time lung tumor motion tracking in SI direction with continuous ultrasound and periodic CBPI was demonstrated. The real‐time estimation of the target position from the two streams for lung cancer patients would enable respiration gating or tracking during SBRT.
Quantifying ventilation change due to radiation therapy using 4DCT Jacobian calculations
Authors: Patton Taylor J. , Gerard Sarah E. , Shao Wei , Christensen Gary E. , Reinhardt Joseph M. , Bayouth John E.
Published: July 2018

Purpose

Regional ventilation and its response to radiation dose can be estimated using four‐dimensional computed tomography (4DCT) and image registration. This study investigated the impact of radiation therapy (RT) on ventilation and the dependence of radiation‐induced ventilation change on pre‐RT ventilation derived from 4DCT.

Methods and materials

Three 4DCT scans were acquired from each of 12 subjects: two scans before RT and one scan 3 months after RT. The 4DCT datasets were used to generate the pre‐RT and post‐RT ventilation maps by registering the inhale phase image to the exhale phase image and computing the Jacobian determinant of the resulting transformation. The ventilation change between pre‐RT and post‐RT was calculated by taking a ratio of the post‐RT Jacobian map to the pre‐RT Jacobian map. The voxel‐wise ventilation change between pre‐ and post‐RT was investigated as a function of dose and pre‐RT ventilation.

Results

Lung regions receiving over 20 Gy exhibited a significant decrease in function (3.3%, P < 0.01) compared to those receiving less than 20 Gy. When the voxels were stratified into high and low pre‐RT function by thresholding the Jacobian map at 10% volume expansion (Jacobian = 1.1), high‐function voxels exhibited 4.8% reduction in function for voxels receiving over 20 Gy, a significantly greater decline (P = 0.037) than the 2.4% reduction in function for low‐function voxels. Ventilation decreased linearly with dose in both high‐function and low‐function regions. High‐function regions showed a significantly larger decline in ventilation (P ≪ 0.001) as dose increased (1.4% ventilation reduction/10 Gy) compared to low‐function regions (0.3% ventilation reduction/10 Gy). With further stratification of pre‐RT ventilation, voxels exhibited increasing dose‐dependent ventilation reduction with increasing pre‐RT ventilation, with the largest pre‐RT Jacobian bin (pre‐RT Jacobian between 1.5 and 1.6) exhibiting a ventilation reduction of 4.8% per 10 Gy.

Conclusions

Significant ventilation reductions were measured after radiation therapy treatments, and were dependent on the dose delivered to the tissue and the pre‐RT ventilation of the tissue. For a fixed radiation dose, lung tissue with high pre‐RT ventilation experienced larger decreases in post‐RT ventilation than lung tissue with low pre‐RT ventilation.
Are the eigenvalues of the B‐spline isogeometric analysis approximation of −Δu = λu known in almost closed form?
Authors: Ekström Sven‐Erik , Furci Isabella , Garoni Carlo , Manni Carla , Serra‐Capizzano Stefano , Speleers Hendrik
Published: July 2018

We consider the B‐spline isogeometric analysis approximation of the Laplacian eigenvalue problem −Δu = λu over the d‐dimensional hypercube (0,1)d. By using tensor‐product arguments, we show that the eigenvalue–eigenvector structure of the resulting discretization matrix is completely determined by the eigenvalue–eigenvector structure of the matrix
arising from the isogeometric analysis approximation based on B‐splines of degree p of the unidimensional problem
. Here, n is the mesh fineness parameter, and the size of
is N(n,p) = n + p − 2. In previous works, it was established that the normalized sequence
enjoys an asymptotic spectral distribution described by a function ep(θ), the so‐called spectral symbol. The contributions of this paper can be summarized as follows:

We prove several important analytic properties of the spectral symbol ep(θ). In particular, we show that ep(θ) is monotone increasing on [0,π] for all p ≥ 1 and that ep(θ)→θ2 uniformly on [0,π] as p→∞.

For p = 1 and p = 2, we show that
belongs to a matrix algebra associated with a fast unitary sine transform, and we compute eigenvalues and eigenvectors of
. In both cases, the eigenvalues are given by ep(θj,n), j = 1,…,n + p − 2, where θj,n = jπ/n.

For p ≥ 3, we provide numerical evidence of a precise asymptotic expansion for the eigenvalues of
, excluding the largest
eigenvalues (the so‐called outliers). More precisely, we numerically show that for every p ≥ 3, every integer α ≥ 0, every n, and every
,

urn:x-wiley:nla:media:nla2198:nla2198-math-0010
where

the eigenvalues of
are arranged in ascending order,
;

is a sequence of functions from [0,π] to
, which depends only on p;

h = 1/n and θj,n = jπh for j = 1,…,n; and

is the remainder, which satisfies
for some constant
depending only on α and p.

We also provide a proof of this expansion for α = 0 and j = 1,…,N(n,p) −(4p − 2), where 4p − 2 represents a theoretical estimate of the number of outliers
.

We show through numerical experiments that, for p ≥ 3 and k ≥ 1, there exists a point θ( p,k) ∈ (0,π) such that
vanishes on [0,θ( p,k)]. Moreover, as it is suggested by the numerics of this paper, the infimum of θ(p,k) over all k ≥ 1, say yp, is strictly positive, and the equation
holds numerically whenever θj,n < θ( p), where θ( p) is a point in (0,yp] which grows with p.

For p ≥ 3, based on the asymptotic expansion in the above item 3, we propose a parallel interpolation–extrapolation algorithm for computing the eigenvalues of
, excluding the
outliers. The performance of the algorithm is illustrated through numerical experiments. Note that, by the previous item 4, the algorithm is actually not necessary for computing the eigenvalues corresponding to points θj,n < θ( p).
A three‐scale compressible microsphere model for hyperelastic materials
Authors: Dal Hüsnü , Cansız Bariş , Miehe Christian
Published: July 2018

This paper presents a seminumerical homogenization framework for porous hyperelastic materials that is open for any hyperelastic microresponse. The conventional analytical homogenization schemes do apply to a limited number of elementary hyperelastic constitutive models. Within this context, we propose a general numerical scheme based on the homogenization of a spherical cavity in an incompressible unit hyperelastic solid sphere, which is denoted as the mesoscopic representative volume element (mRVE). The approach is applicable to any hyperelastic micromechanical response. The deformation field in the sphere is approximated via nonaffine kinematics proposed by Hou and Abeyaratne (JMPS 40:571‐592,1992). Symmetric displacement boundary conditions driven by the principal stretches of the deformation gradient are applied on the outer boundary of the mRVE. The macroscopic quantities, eg, stress and moduli expressions, are obtained by analytically derived pointwise geometric transformations. The macroscopic expressions are then computed numerically through quadrature rules applied in the radial and surface directions of the sphere. A three‐scale compressible microsphere model is derived from the developed seminumerical homogenization framework where the micro‐meso transition is based on the nonaffine microsphere model at every point of the mRVE. The numerical scheme developed for the derivation of macroscopic homogenized stresses and moduli terms as well as the modeling capability of the three‐scale microsphere model is investigated through representative boundary value problems.
Coupling of finite element and plane waves discontinuous Galerkin methods for time‐harmonic problems
Authors: Gaborit M. , Dazel O. , Göransson P. , Gabard G.
Published: July 2018

A coupling approach is presented to combine a wave‐based method to the standard finite element method. This coupling methodology is presented here for the Helmholtz equation but it can be applied to a wide range of wave propagation problems. While wave‐based methods can significantly reduce the computational cost, especially at high frequencies, their efficiency is hampered by the need to use small elements to resolve complex geometric features. This can be alleviated by using a standard finite element model close to the surfaces to model geometric details and create large, simply‐shaped areas to model with a wave‐based method. This strategy is formulated and validated in this paper for the wave‐based discontinuous Galerkin method together with the standard finite element method. The coupling is formulated without using Lagrange multipliers and results demonstrate that the coupling is optimal in that the convergence rates of the individual methods are maintained.
Numerical solution a class of 2D fractional optimal control problems by using 2D Müntz‐Legendre wavelets
Authors: Rahimkhani Parisa , Ordokhani Yadollah
Published: July 2018

In this paper, a method for finding an approximate solution of a class of 2D fractional optimal control problems with fractional‐order dynamical system is discussed. In the proposed method, the fractional derivative is expressed in the Caputo sense. The method consists of expanding unknown functions as the elements of two‐dimensional (2D) Müntz‐Legendre wavelets. The 2D Müntz‐Legendre wavelets are constructed and their properties are presented. The operational matrix of fractional‐order integration for these wavelets is utilized to reduce the solution of 2D fractional optimal control problem to an optimization problem, which can then be solved easily. Some results concerning the error analysis are obtained. Finally, two illustrative test problems are included to demonstrate the validity and applicability of the technique. Moreover, our achievements are compared with the previous results to show the superiority of the proposed method.
Deletion of cadherin‐17 enhances intestinal permeability and susceptibility to intestinal tumour formation
Authors: Chang Ya‐Yun , Yu Linda Chia‐Hui , Yu I‐Shing , Jhuang Yu‐Lin , Huang Wei‐Ju , Yang Ching‐Yao , Jeng Yung‐Ming
Published: July 2018

Cadherin‐17 is an adhesion molecule expressed specifically in intestinal epithelial cells. It is frequently underexpressed in human colorectal cancer. The physiological function of cadherin‐17 and its role in tumourigenesis have not yet been determined. We used the transcription activator‐like effector nuclease technique to generate a Cdh17 knockout (KO) mouse model. Intestinal tissues were analysed with histological, immunohistochemical and ultrastructural methods. Colitis was induced by oral administration of dextran sulphate sodium (DSS), and, to study effects on intestinal tumourigenesis, mice were given azoxymethane (AOM) and DSS to induce colitis‐associated cancer. Cdh17 KO mice were viable and fertile. The histology of their small and large intestines was similar to that of wild‐type mice. The junctional architecture of the intestinal epithelium was preserved. The loss of cadherin‐17 resulted in increased permeability and susceptibility to DSS‐induced colitis. The AOM/DSS model demonstrated that Cdh17 KO enhanced tumour formation and progression in the intestine. Increased nuclear translocation of Yap1, but not of β‐catenin, was identified in the tumours of Cdh17 KO mice. In conclusion, cadherin‐17 plays a crucial role in intestinal homeostasis by limiting the permeability of the intestinal epithelium. Cadherin‐17 is also a tumour suppressor for intestinal epithelia. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The impact of fetal endoscopic tracheal occlusion in isolated left‐sided congenital diaphragmatic hernia on left‐sided cardiac dimensions
Authors: Dhillon Gurpreet S. , Maskatia Shiraz A. , Loar Robert W. , Colquitt John L. , Mehollin‐Ray Amy R. , Ruano Rodrigo , Belfort Michael A. , Olutoye Oluyinka O. , Kailin Joshua A.
Published: July 2018

Objectives

Fetal endoscopic tracheal occlusion (FETO) is offered to fetuses with congenital diaphragmatic hernia (CDH) and severe lung hypoplasia to promote lung growth and may secondarily affect left heart growth. The effects of FETO on left heart hypoplasia (LHH) are not described post‐CDH repair.

Methods

A retrospective analysis was performed for fetuses with left‐sided CDH who underwent FETO and severity‐matched controls from 2007 to 2016 at our institution. Echocardiographic, ultrasound, and MRI data were reviewed. Left heart dimensions were assessed prenatally and postnatally. Primary clinical outcome evaluated was death.

Results

Twelve FETO patients and 18 controls were identified. Fetal LHH was noted in both groups and worsened after FETO. Postnatal mitral valve dimensions were larger in the FETO group pre‐CDH repair (P = .03). Post‐CDH repair, mitral valve and left ventricular dimensions were not significantly different between groups (P = .79 and P = .63 respectively) while FETO aortic valve dimensions were smaller (P = .04). Extracorporeal membrane oxygenation use was lower in the FETO group. No associations were found between left heart dimensions and outcomes.

Conclusion

Although increased lung growth was seen after FETO, fetal LHH persisted with relative normalization seen post‐repair. Persistent LHH post‐FETO could be secondary to a small contribution of pulmonary venous return to the fetal left heart and increased intrathoracic pressures post‐FETO.
Modality‐specific exercise guidelines and quality of life in kidney cancer survivors: A cross‐sectional study
Authors: Trinh Linda , Strom Dominick A. , Wong Jaime N. , Courneya Kerry S.
Published: July 2018

Objectives

Few exercise oncology trials have compared aerobic with strength exercise or compared combined exercise (ie, aerobic and strength training) with aerobic only or strength only. It is unknown what single or combined exercise modality is optimal for quality of life (QoL) in cancer survivors. The purpose of this study is to estimate the prevalence of meeting the combined and independent aerobic and strength exercise guidelines in kidney cancer survivors (KCS) and determine any associations with QoL.

Methods

One thousand nine hundred eighty‐five KCS were identified through a provincial registry in Canada and mailed a survey including exercise and QoL scales.

Results

Completed surveys were received from 703 KCS. Only 10.1% of KCS reported meeting the combined exercise guidelines. Analyses of covariance indicated that, for most QoL outcomes (eg, Functional Assessment of Cancer Therapy—General and Functional Assessment of Cancer Therapy—Fatigue), meeting the combined exercise guideline was superior to meeting either single modality guideline that, in turn, were superior to meeting neither guideline. For the primary outcome of the Trial Outcome Index‐Fatigue, meeting the combined exercise guideline was superior to meeting (a) neither guideline (P < 0.001), (b) the strength‐only guideline (P = 0.021), and (c) the aerobic‐only guideline (P = 0.051). In turn, the aerobic and strength exercise only guidelines were superior to meeting neither guideline (P < 0.001 for aerobic; P = 0.045 for strength) but were not different from each other (P = 0.50).

Conclusions

Meeting the combined exercise guideline has favorable associations with QoL in KCS, however, very few KCS are meeting the combined guideline.
Band Alignment of Al2O3 Layer Deposited NO and SO2 Exposed (001) H‐Diamond Heterointerfaces Studied by Synchrotron Radiation X‐Ray Photoelectron Spectroscopy
Authors: Saha Niloy C. , Takahashi Kazutoshi , Imamura Masaki , Kasu Makoto
Published: July 2018

The interfacial energy band alignment of the interface between H‐terminated diamond, exposed to either NO or SO2, and an Al2O3 layer is studied using synchrotron radiation X‐ray photoelectron spectroscopy (XPS) and X‐ray absorption near‐edge structure (XANES) measurements. From the results, type II band alignment is determined for both the Al2O3/NO/H‐diamond and the Al2O3/SO2/H‐diamond heterointerfaces. The valence band offsets are determined to be 3.7 eV for the Al2O3/NO/H‐diamond heterointerface and 3.5 ± 0.1 eV for the Al2O3/SO2/H‐diamond heterointerface. XPS spectra indicate that the NO and SO2 decompose on the H‐diamond surface, and XANES measurements demonstrate the formation of oxygen related interface states.
Protocatechuic acid inhibits the growth of ovarian cancer cells by inducing apoptosis and autophagy
Authors: Xie Zhoufan , Guo Ziyan , Wang Yun , Lei Jiachuan , Yu Jianqing
Published: July 2018

Protocatechuic acid (PCA), present in many fruits and vegetables, exhibited various biological activities. Here, we provided evidence that it could be developed as a potential chemotherapeutic agent against human ovarian cancer. We found that PCA treatment significantly reduced the cell viability and colony formation of OVCAR‐3, SKOV‐3, and A2780 cells. OVCAR‐3 cells were selected as a test model system for investigating molecular mechanism. PCA treatment induced cell cycle arrest in G2/M phase, the activation of poly (ADP‐ribose) polymerase (PARP) and caspase‐3, the upregulation of Bax and downregulation of Bcl‐2 in OVCAR‐3 cells. We also observed that PCA treatment significantly caused upregulation of autophagy‐related protein LC3‐II and induced GFP‐LC3 puncta formation. Furthermore, cotreatment with PCA and autophagy inhibitor attenuated the cytotoxicity induced by PCA in OVCAR‐3 cells. Moreover, our results showed that PCA increased the intracellular levels of glutathione and decreased intracellular reactive oxygen species that might be related to the inhibition effect of PCA on OVCAR‐3 cells. Our data revealed that PCA could modulate apoptosis and autophagy, suggesting the potential of PCA for chemoprevention and chemotherapy of ovarian cancer.
An Orbitrap‐based laser desorption/ablation mass spectrometer designed for spaceflight
Authors: Arevalo Ricardo , Selliez Laura , Briois Christelle , Carrasco Nathalie , Thirkell Laurent , Cherville Barnabé , Colin Fabrice , Gaubicher Bertrand , Farcy Benjamin , Li Xiang , Makarov Alexander
Published: July 2018

Rationale

The investigation of cryogenic planetary environments as potential harbors for extant life and/or contemporary sites of organic synthesis represents an emerging focal point in planetary exploration. Next generation instruments need to be capable of unambiguously determining elemental and/or molecular stoichiometry via highly accurate mass measurements and the separation of isobaric interferences.

Methods

An Orbitrap™ analyzer adapted for spaceflight (referred to as the CosmOrbitrap), coupled with a commercial pulsed UV laser source (266 nm), was used to successfully characterize a variety of planetary analog samples via ultrahigh resolution laser desorption/ablation mass spectrometry. The materials analyzed in this study include: jarosite (a hydrous sulfate detected on Mars); magnesium sulfate (a potential component of the subsurface ocean on Europa); uracil (a nucleobase of RNA); and a variety of amino acids.

Results

The instrument configuration tested here enables: measurement of major elements and organic molecules with ultrahigh mass resolution (m/Δm ≥ 120,000, FWHM); quantification of isotopic abundances with <1.0% (2σ) precision; and identification of highly accurate masses within 3.2 ppm of absolute values. The analysis of a residue of a dilute solution of amino acids demonstrates the capacity to detect twelve amino acids in positive ion mode at concentrations as low as ≤1 pmol/mm2 while maintaining mass resolution and accuracy requirements.

Conclusions

The CosmOrbitrap mass analyzer is highly sensitive and delivers mass resolution/accuracy unmatched by any instrument sent into orbit or launched into deep space. This prototype instrument, which maps to a spaceflight implementation, represents a mission‐enabling technology capable of advancing planetary exploration for decades to come.
Organocatalytic Asymmetric Cascade Reaction of γ‐Substituted Deconjugated Butenolides with o‐Formyl‐β‐nitrostyrene
Authors: Deepake Siddharth K. , Lanjewar Atul B. , Thatikonda Thanusha , Gonnade Rajesh G. , Das Utpal
Published: July 2018

An efficient chemo‐, diastereo‐ and enantio‐selective cascade synthesis of functionalized indanols bearing four contiguous stereogenic centres has been developed via the reaction of β,γ‐butenolides with o‐formyl‐β‐nitrostyrenes in the presence of bi‐functional hydrogen‐bonding catalyst. Indanol derivatives containing γ,γ‐disubstituted butenolides were obtained in good yields and with moderate to high enantioselectivities/diastereoselectivities.
Cost‐efficient and network‐aware dynamic repartitioning‐based algorithms for scheduling large‐scale graphs in cloud computing environments
Authors: Heidari Safiollah , Buyya Rajkumar
Published: July 2018

Large amount of data that is generated by Internet and enterprize applications are stored in the form of graphs. Graph processing systems are broadly used in enterprizes to process such data. With the rapid growth in mobile and social applications and complicated connections of Internet websites, massive concurrent operations need to be handled. On the other hand, the intrinsic structure and the size of real‐world graphs make distributed processing of graphs more challenging. Low balanced communication and computation, low preprocessing overhead, low memory footprint, and scalability should be offered by distributed graph analytics frameworks. Moreover, the effects of network factors such as bandwidth and traffic as well as monetary cost of processing such large‐scale graphs and the mutual impact of these elements have been less studied. To address these issues, we proposed two dynamic repartitioning algorithms that consider network factors, affecting public cloud environments to decrease the monetary cost of processing. A new classification of graph algorithms and processing is also introduced, which will be used to choose the best strategy for processing at any operation. We plugged these algorithms to our extended graph processing system (iGiraph) and compared them with those supported in other graph processing systems such as Giraph and Surfer on Australian National Cloud Infrastructure. We observed that up to 30% faster execution time, up to 50% network traffic decline, and more than 50% cost reduction are achieved by our algorithms compared to a framework such as the popular Giraph.
Interplay of Electronic and Steric Effects of R2PH (R = tBu, o‐tolyl) in Reactions with Triruthenium Dodecacarbonyl
Authors: Böttcher Hans‐Christian , Graf Marion , Mayer Peter
Published: July 2018

The reaction of [Ru3(CO)12] with P(o‐tolyl)2H (molar ratio of 1 to 2) in refluxing THF afforded the electron‐precise metal cluster [Ru3(μ‐H)2(μ‐P{o‐tolyl}2)2(CO)8] (3). This reaction behavior is comparable to that using the secondary phosphane PtBu2H operating with the same molar ratio. As shown in earlier work, the ruthenium carbonyl reacted with an excess of PtBu2H under similar conditions with cluster degradation affording the coordinatively unsaturated complex [Ru2(μ‐H)(μ‐PtBu2)(PtBu2H)2(CO)4]. We found that the reaction using similar reaction conditions with P(o‐tolyl)2H in excess did not result in such a reactive dinuclear species. Here compound 3 was formed in a first step, which reacted with excess of the phosphane affording the new cluster [Ru3(μ‐H)2(μ‐P{o‐tolyl}2)2(P{o‐tolyl}2H)2(CO)6] (2). The molecular structures of 2 and 3 in the solid were confirmed by single‐crystal X‐ray analysis. Moreover, the 31P NMR spectra of the new compounds showed coalescence phenomena on the NMR time scale caused by a restricted rotation about the P–C bonds, and, presumably, about Ru–P bonds, within the phosphane and phosphanido ligands.
Conformal manifolds with boundaries or defects
Authors: Karch Andreas , Sato Yoshiki
Published: July 2018

Abstract

We discuss conformal manifolds for conformal field theories with boundaries or defects. Using conformal perturbation theory we derive constraints on coefficients appearing in the boundary operator product expansion and three-point functions that need to be satisfied for the existence of marginal couplings. We present several explicit examples where we confirm that β-functions vanish using a position space regularization, differential regularization. Where possible, we confirm that our β-function results agree with the existing literature.
Can we observe fuzzballs or firewalls?
Authors: Guo Bin , Hampton Shaun , Mathur Samir D.
Published: July 2018

Abstract

In the fuzzball paradigm the information paradox is resolved because the black hole is replaced by an object with no horizon. One may therefore ask if observations can distinguish a traditional hole from a fuzzball. We give arguments for why the fuzzball structure should lie close to the horizon; i.e., it should be a ‘tight’ fuzzball. We find: (a) It is very difficult to reflect quanta off the surface of such a fuzzball, mainly because geodesics starting near the horizon radius cannot escape to infinity unless their starting direction is very close to radial. (b) If infalling particles interact with the emerging radiation before they are engulfed by the horizon, then we say that we have a ‘firewall behavior’. We consider several types of interactions, but find no evidence for firewall behavior in any theory that obeys causality. (c) Photons with wavelengths larger than the black hole radius can be

scattered off the emerging radiation, but a very small fraction of the backscattered photons will be able to escape back to infinity.
Understanding and Practices of Gynaecologists Related to Breast Cancer Screening, Detection, Treatment and Common Breast Diseases: A Study from India
Authors: Singh Gitika N. , Agarwal Aastha , Jain Vinod , Kumar Priti
Published: July 2018

Background

The knowledge of breast cancer risk factors and screening practices in a community is largely influenced by the practising gynaecologist in that area. We assessed the understanding and knowledge of gynaecologists about breast cancer: screening, risk factors, clinical signs, management and common benign breast diseases.

Methodology

This cross‐sectional study was carried out in Uttar Pradesh, India, from April to September 2017. One hundred and fifty‐two gynaecologists were assessed using a self‐designed and validated questionnaire to assess the knowledge of risk factors, clinical signs, screening practices and management of breast cancer as well as common benign breast diseases. Further, the results were compared based on their education: undergraduates (UGs; no residency experience in obstetrics and gynaecology) versus postgraduates (PGs; residency experience in obstetrics and gynaecology).

Results

67 and 82.2% of gynaecologists possess excellent to very good knowledge of risk factors and clinical signs of breast cancer, respectively. The knowledge of PGs seems to be better than UGs (p < 0.01). 84.9% participants were aware that breast cancer screening decreases breast cancer‐related mortality, and 61.2% considered CBE as most relevant screening investigation (66.1% PGs and 41.9% UGs; p = 0.04). 30.2% regularly offer breast cancer screening at their centre. 58.5% did not consider screening mammography as cost‐effective for their patients (57.9% PGs and 61.3% UGs; p = 0.72), and 41.4% considered it to be a time‐consuming process (39.7% PGs and 48.4% UGs; p = 0.38). 99.3% like to follow up a patient with familial breast cancer by themselves, and 0.7% like to refer them to specialist. 51.9% gynaecologists were convinced of breast conservation surgery (BCS) as a surgical option, however 51.3% feared leaving diseased breast behind.

Conclusion

Despite the knowledge regarding risk factors, clinical signs and treatment of breast cancer and benign breast diseases was found adequate amongst the gynaecologists, this did not apply to their clinical practice. Structured and continuous training of gynaecologists is needed to improve the outcome of patients with breast diseases in terms of better management and reference.
Paediatric Osteomyelitis in Fiji
Authors: Munshi Basharat , MacFater Wiremu , Hill Andrew G. , McCaig Eddie H.
Published: July 2018

Introduction

Osteomyelitis can lead to significant morbidity and long‐term disability if early treatment is not initiated in a timely manner. For developing countries this can lead to a significant burden on the healthcare system. This study aims to describe the demographic variables, aetiology and outcomes of treatment and to calculate the incidence of paediatric osteomyelitis in Fiji. The micro‐organism profile and the outcomes for treatment were analysed.

Methods

This is a retrospective review of medical records of all paediatric patients presenting to hospitals in Fiji over a 5‐year period (2006–2010) with a diagnosis of osteomyelitis. Data were collected from the three divisional hospitals in Fiji (Colonial War Memorial Hospital, Lautoka Hospital and Labasa Hospital).

Results

Two hundred and twenty patients were identified. An annual incidence of 18.1 cases/100,000 paediatric population was identified. The highest incidence was in the itaukei (ethnic Fijian) population (21 cases/100,000). Males were at a higher risk of developing osteomyelitis (20.8/105 vs. 10.7/105). Staphylococcus Aureus was identified in 86% of all positive blood and 81% of all positive pus cultures, and it was sensitive to cloxacillin in 100% of cases. The most common factor identified preceding the development of osteomyelitis was trauma (55%) followed by skin sepsis (32%). Fifty‐four per cent of the cases had chronic osteomyelitis, and the most common mode of presentation was in the form of an abscess (48%) followed by sinus/sequestrum (24%). The age group most commonly affected was between 5 and 9 years of age (19.6/105). Children with chronic osteomyelitis were more likely to require operative intervention in addition to antibiotics as compared to acute osteomyelitis (85 vs. 24%). The success rate of treating acute osteomyelitis was 92% compared to 61% for chronic osteomyelitis.

Conclusion

Paediatric osteomyelitis poses a significant problem in Fiji, especially in the male, ethnic Fijian population between 5 and 9 years of age. The chance of complete resolution after treatment of acute osteomyelitis is very good. Therefore, interventions aimed at early diagnosis and treatments are required.
Assessment of adolescent optimism: Measurement invariance across gender and race/ethnicity
Authors: Webber Kristina C. , Smokowski Paul R.
Published: July 2018

Introduction

Optimism is viewed as an important resource for resilience and is associated with various wellbeing outcomes, yet few measures of optimism have been validated for use with adolescents. The aim of this study was to (a) test the factor structure invariance of the School Success Profile Success Orientation scale across gender and four racial/ethnic groups and (b) estimate group‐level differences in optimism.

Methods

Data from a diverse sample of adolescents (N = 2063; mean 12.3 years; 52% female) from the southeastern United States were examined using multiple‐group confirmatory factor analysis. Models for configural, metric, and scalar invariance were tested using WLSMV estimation in Mplus.

Results

Confirmatory factor analysis supported the hypothesized one‐factor model and indicated scalar invariance across gender and the four racial/ethnic (i.e., African American, Caucasian, Hispanic/Latino, Native American) groups. Cross‐group comparisons of latent factor means indicated statistically significant differences in self‐reported optimism. Female respondents reported higher optimism than males. Among the four racial/ethnic groups, African American youth reported the highest optimism levels. Native American youth reported higher optimism than Caucasian and Hispanic/Latino youth.

Conclusions

Results suggest the Success Orientation scale is appropriate for many assessment and evaluation purposes, including the assessment of optimism across gender and race/ethnicity and the investigation of substantive questions regarding cross‐cultural differences in adolescents' expectations of the future.
Interactions between eye movements and posture in children with neurodevelopmental disorders
Authors: Bucci Maria Pia , Goulème Nathalie , Dehouck Delphine , Stordeur Coline , Acquaviva Eric , Septier Mathilde , Lefebvre Aline , Gerard Christophe‐Loïc , Peyre Hugo , Delorme Richard
Published: July 2018

In everyday life, our activities frequently involve the simultaneous performance of two or more tasks. Sharing attention between two concurrent tasks may result in a decrease in performance specifically among children with neurodevelopmental disorders. The objective of the study was to determine whether the influence of postural conditions (sitting condition, single task; standing condition, dual task) on eye movement performances on three visual tasks with high attentional load (visually‐guided saccade task, memory‐guided saccade task and fixation task) was different in children with neurodevelopmental disorders (attention deficit and hyperactive disorder, dyslexia, and high functioning autism spectrum disorder) when compared to typically developing children. One hundred and four children (26 per group, sex‐age‐ and IQ‐matched groups) were evaluated. We found that for the fixation task only, the three groups of children with neurodevelopmental disorders had poorer eye movements performances in the standing condition compared to the sitting condition while no such difference was found for typically developing children. We suggest that children with neurodevelopmental disorders have fewer attentional resources available for performing correctly oculomotor tasks with high attentional load leading to impairment of these tasks for maintaining a good level of postural stability.
How to Podcast in Archaeology
Authors: Amundsen Colin P. , Belmonte Cristina
Published: July 2018

The problem for archaeologists doing public outreach could be that we do not know who our audience is. Marketing to just the public at large is an extremely broad approach filled with the pitfalls of not engaging enough of the public, so it might be necessary to first find out who within the general public would have the most interest in your discovery and then tailor your presentation to that audience. At the podcast Cooking with Archaeologists we are using digital media, social media marketing, and our experience from the business world to do just that. Podcasting has been a trial-and-error project filled with uncertainty and doubt, and for archaeologists engaged in public archaeology it might be a practical approach to reaching the public and a medium to build an engaged and interested audience. In this “how-to” article, we will reveal what we have learned from this exciting and somewhat demanding venture and suggest how podcasting is a democratizing venture that connects the public to archaeology and the archaeologist.
The Living and the Dead Entwined in Virtual Space
Authors: Huffer Damien
Published: July 2018

Teaching and public engagement with the results and implications of bioarchaeological research have increasingly attracted more varied and social media-savvy audiences. Since 2010, the social media platform Instagram has also flourished, with millions of users forming untold numbers of communities of practice. Here, I seek to address the intersection of bioarchaeology and the virtual “stage” that social media represents. How is the discipline of bioarchaeology and the act of being a bioarchaeologist represented on Instagram? How do practicing bioarchaeologists (and enthusiastic supporters of the field) communicate about their own and others’ research, fieldwork, laboratory work, et cetera? With ever-greater amounts of scientific communication and public outreach conducted over social media (e.g., Gura 2013; Kling and McKim 2000; Wheat et al. 2013), it is worth investigating how the living who study the dead interact with each other, form community, and engage online audiences that increasingly contain descendants of the dead being studied. The review below is short; hence, the nature and depth of inquiry is restricted. Nevertheless, enough data are available to allow broader speculation and to suggest that there is space for more concerted future research.
On concentration properties of partially observed chaotic systems
Authors: Paulin Daniel , Jasra Ajay , Crisan Dan , Beskos Alexandros
Published: July 2018

In this paper we present results on the concentration properties of the smoothing and filtering distributions of some partially observed chaotic dynamical systems. We show that, rather surprisingly, for the geometric model of the Lorenz equations, as well as some other chaotic dynamical systems, the smoothing and filtering distributions do not concentrate around the true position of the signal, as the number of observations tends to ∞. Instead, under various assumptions on the observation noise, we show that the expected value of the diameter of the support of the smoothing and filtering distributions remains lower bounded by a constant multiplied by the standard deviation of the noise, independently of the number of observations. Conversely, under rather general conditions, the diameter of the support of the smoothing and filtering distributions are upper bounded by a constant multiplied by the standard deviation of the noise. To some extent, applications to the three-dimensional Lorenz 63 model and to the Lorenz 96 model of arbitrarily large dimension are considered.
Spectral bounds in random graphs applied to spreading phenomena and percolation
Authors: Lemonnier Rémi , Scaman Kevin , Vayatis Nicolas
Published: July 2018

In this paper we derive nonasymptotic upper bounds for the size of reachable sets in random graphs. These bounds are subject to a phase transition phenomenon triggered by the spectral radius of the hazard matrix, a reweighted version of the adjacency matrix. Such bounds are valid for a large class of random graphs, called local positive correlation (LPC) random graphs, displaying local positive correlation. In particular, in our main result we state that the size of reachable sets in the subcritical regime for LPC random graphs is at most of order O(√n), where n is the size of the network, and of order O(n2/3) in the critical regime, where the epidemic thresholds are driven by the size of the spectral radius of the hazard matrix with respect to 1. As a corollary, we also show that such bounds hold for the size of the giant component in inhomogeneous percolation, the SIR model in epidemiology, as well as for the long-term influence of a node in the independent cascade model.
On mutations in the branching model for multitype populations
Authors: Chaumont Loïc , Nguyen Thi Ngoc Anh
Published: July 2018

The forest of mutations associated to a multitype branching forest is obtained by merging together all vertices in each of its clusters and by preserving connections between them. (Here, by cluster, we mean a maximal connected component of the forest in which all vertices have the same type.) We first show that the forest of mutations of any multitype branching forest is itself a branching forest. Then we give its progeny distribution and we describe some of its crucial properties in terms of the initial progeny distribution. We also obtain the limiting behaviour of the number of mutations both when the total number of individuals tends to ∞ and when the number of roots tends to ∞. The continuous-time case is then investigated by considering multitype branching forests with edge lengths. When mutations are nonreversible, we give a representation of their emergence times which allows us to describe the asymptotic behaviour of the latter, under certain conditions on the mutation rates. These results have potential relevance for emergence of mutations in population cells, particularly for genetic evolution of cancer or development of infectious diseases.
Understanding the Impacts of Maritime Disruption Transportation to Hospital-Based Acute Health Care Supplies and Personnel in Coastal and Geographically Isolated Communities
Authors: Errett Nicole A. , Tanner Alexa , Shen Xuesi , Chang Stephanie E.
Published: July 2018

Objective

This study aimed to identify maritime transportation disruption impacts on available health care supplies and workers necessary to deliver hospital-based acute health care in geographically isolated communities post-disaster.

Methods

Semi-structured interviews were conducted with 25 key informants knowledgeable about the hospital-based acute health care supply chain and workforce emergency management plans and procedures in 2 coastal communities in British Columbia. These locations were accessed primarily through maritime transportation, including one urban center and one smaller, more remote community. Interview transcriptions were thematically analyzed.

Results

Critical vulnerabilities to hospital-based acute health care delivery due to a maritime transportation disruption identified include lack of information about the existing supply chain, lack of formal plans and agreements, and limited local supply storage and workforce capacity. Measures to decrease vulnerability and enhance system capacity can be fostered to enhance acute health care system resilience for these and other geographically isolated communities.

Conclusions

A maritime transportation disruption has the potential to impact the availability of hospital-based health care supplies and health care personnel necessary to deliver acute health care in coastal communities post-disaster. Multisector engagement is required to address complex interdependencies and competing priorities in emergency response. Additional research and public-private collaboration is necessary to quantify potential impacts of maritime transportation disruption on the acute health care system. (Disaster Med Public Health Preparedness. 2019;13:440-448)
Trainee experience in diagnosis and management of personality disorders
Authors: Wallace R. , Rush G.
Published: July 2018

The diagnosis and management of personality disorders continues to evolve and develop alongside psychiatry internationally, however, not always in a linear fashion. Trainees working in a variety of clinical areas have regular exposure to personality disorder presentations. Psychiatry training bodies continue to adapt their training structure and curriculum, however, there seems to be a lack of sufficient emphasis with regards this area. We are now embarking on a new diagnostic system for personality disorders; this may impact on our clinical practice and perspective of these patients. The role of psychiatrists in diagnosing and managing personality disorders can be unclear at times and may benefit from on-going reflection and standardization.
Recovering a hidden community beyond the Kesten–Stigum threshold in O(|E|log*|V|) time
Authors: Hajek Bruce , Wu Yihong , Xu Jiaming
Published: July 2018

Community detection is considered for a stochastic block model graph of n vertices, with K vertices in the planted community, edge probability p for pairs of vertices both in the community, and edge probability q for other pairs of vertices. The main focus of the paper is on weak recovery of the community based on the graph G, with o(K) misclassified vertices on average, in the sublinear regime n1-o(1) ≤ K ≤ o(n). A critical parameter is the effective signal-to-noise ratio λ = K2(p - q)2 / ((n - K)q), with λ = 1 corresponding to the Kesten–Stigum threshold. We show that a belief propagation (BP) algorithm achieves weak recovery if λ > 1 / e, beyond the Kesten–Stigum threshold by a factor of 1 / e. The BP algorithm only needs to run for log*n + O(1) iterations, with the total time complexity O(|E|log*n), where log*n is the iterated logarithm of n. Conversely, if λ ≤ 1 / e, no local algorithm can asymptotically outperform trivial random guessing. Furthermore, a linear message-passing algorithm that corresponds to applying a power iteration to the nonbacktracking matrix of the graph is shown to attain weak recovery if and only if λ > 1. In addition, the BP algorithm can be combined with a linear-time voting procedure to achieve the information limit of exact recovery (correctly classify all vertices with high probability) for all K ≥ (n / logn) (ρBP + o(1)), where ρBP is a function of p / q.
General drawdown-based de Finetti optimization for spectrally negative Lévy risk processes
Authors: Wang Wenyuan , Zhou Xiaowen
Published: July 2018

For spectrally negative Lévy risk processes we consider a general version of de Finetti's optimal dividend problem in which the ruin time is replaced with a general drawdown time from the running maximum in its value function. We identify a condition under which a barrier dividend strategy is optimal among all admissible strategies if the underlying process does not belong to a small class of compound Poisson processes with drift, for which the take-the-money-and-run dividend strategy is optimal. It generalizes the previous results on dividend optimization from ruin time based to drawdown time based. The associated drawdown functions are discussed in detail for examples of spectrally negative Lévy processes.
Weighted least-squares estimation for the subcritical Heston process
Authors: du Roy de Chaumaray M.
Published: July 2018

We simultaneously estimate the four parameters of a subcritical Heston process. We do not restrict ourselves to the case where the stochastic volatility process never reaches zero. In order to avoid the use of unmanageable stopping times and a natural but intractable estimator, we use a weighted least-squares estimator. We establish strong consistency and asymptotic normality for this estimator. Numerical simulations are also provided, illustrating the favorable performance of our estimation procedure.
On the consistency of the spacings test for multivariate uniformity, including on manifolds
Authors: Henze Norbert
Published: July 2018

We give a simple conceptual proof of the consistency of a test for multivariate uniformity in a bounded set K ⊂ ℝd that is based on the maximal spacing generated by independent and identically distributed points X1, . . ., Xn in K, i.e. the volume of the largest convex set of a given shape that is contained in K and avoids each of these points. Since asymptotic results for the d > 1 case are only availabe under uniformity, a key element of the proof is a suitable coupling. The proof is general enough to cover the case of testing for uniformity on compact Riemannian manifolds with spacings defined by geodesic balls.