bluuebunny/crossref_metadata_2025 huggingface dataset:
Body mass index trajectories from ages 1 to 20: Results from two nationally representative canadian longitudinal cohorts
Authors: Tu Andrew W. , Mâsse Louise C. , Lear Scott A. , Gotay Carolyn C. , Richardson Chris G.
Published: July 2015

Objective

In this study, unique body mass index (BMI) trajectories from ages 1 to 20 years were identified; each trajectory according to socio demographic and family characteristics was described.

Methods

Participants came from two national population surveys (n = 7,253;n = 901) and were aged 1‐6 years at baseline. Children were surveyed biennially over eight waves up to 14‐20 years of age. BMI trajectories by sex and survey cohort were identified by group‐based trajectory modeling. After crossvalidating trajectories between survey cohorts, the characteristics of trajectory membership were assessed by multinomial regression.

Results

Four BMI trajectories were found: low, decreasing, medium, and high. The decreasing trajectory was characterized by an overweight or obese childhood followed by a normal‐weight adolescence. The low, medium, and high trajectories were characterized by growth curves culminating, by age 20, to BMI 22.6, 29.3, and 34.9 kg/m2, respectively, for males and 20.6, 24.5, and 32.0 kg/m2, respectively, for females. Factors associated with the high trajectory included ethnicity and paternal education (female only), large for gestational age, rural area residence, and maternal smoking.

Conclusions

The identification and validation of four major trajectories reflect the heterogeneity in patterns of BMI development from 1 to 20 years.
Effect of poly(l‐lactide)/poly(d‐lactide) block length ratio on crystallization behavior of star‐shaped asymmetric poly(l(d)‐lactide) stereoblock copolymers
Authors: Li Wei , Ma Yan , Fan Zhongyong
Published: July 2015

Effect of Poly(l‐lactide)/Poly(d‐lactide) (PLLA/PDLA) block length ratio on the crystallization behavior of star‐shaped poly(propylene oxide) block poly(d‐lactide) block poly (l‐lactide) (PPO–PDLA–PLLA) stereoblock copolymers with molecular weights (Mn) ranging from 6.2 × 104 to 1.4 × 105 g mol−1 was investigated. Crystallization behaviors were studied utilizing differential scanning calorimetry (DSC), polarized optical microscopy (POM), and wide‐angle X‐ray diffraction (WAXD). Only stereocomplex crystallites formed in isothermal crystallization at 140 to 156°C for all samples. On one hand, the overall crystallization rate decreased as PLLA/PDLA block length ratio increased. As PLLA/PDLA block length ratio increased from 7:7 to 28:7, the value of half time of crystallization (t1/2) delayed form 2.85 to 5.31 min at 140°C. On the other hand, according to the Lauritzen–Hoffman theory, the fold‐surface energy (σe) was calculated. σe decreased from 77.7 to 73.3 erg/cm2 with an increase in PLLA/PDLA block length ratio. Correspondingly increase in nucleation density was observed by the polarized optical microscope. Results indicated that the PLLA/PDLA block length ratio had a significant impact on the crystallization behavior of PPO–PDLA–PLLA copolymers. POLYM. ENG. SCI., 55:2534–2541, 2015. © 2015 Society of Plastics Engineers
A hybrid method for protein–protein interface prediction
Authors: Hwang Howook , Petrey Donald , Honig Barry
Published: July 2015

The growing structural coverage of proteomes is making structural comparison a powerful tool for function annotation. Such template‐based approaches are based on the observation that structural similarity is often sufficient to infer similar function. However, it seems clear that, in addition to structural similarity, the specific characteristics of a given protein should also be taken into account in predicting function. Here we describe PredUs 2.0, a method to predict regions on a protein surface likely to bind other proteins, that is, interfacial residues. PredUs 2.0 is based on the PredUs method that is entirely template‐based and uses known binding sites in structurally similar proteins to predict interfacial residues. PredUs 2.0 uses a Bayesian approach to combine the template‐based scoring of PredUs with a score that reflects the propensities of individual amino acids to be in interfaces. PredUs 2.0 includes a novel protein size dependent metric to determine the number of residues that should be reported as interfacial. PredUs 2.0 significantly outperforms PredUs as well as other published interface prediction methods.
Prediction of stability changes upon mutation in an icosahedral capsid
Authors: Hickman Samuel J. , Ross James F. , Paci Emanuele
Published: July 2015

Identifying the contributions to thermodynamic stability of capsids is of fundamental and practical importance. Here we use simulation to assess how mutations affect the stability of lumazine synthase from the hyperthermophile Aquifex aeolicus, a T = 1 icosahedral capsid; in the simulations the icosahedral symmetry of the capsid is preserved by simulating a single pentamer and imposing crystal symmetry, in effect simulating an infinite cubic lattice of icosahedral capsids. The stability is assessed by estimating the free energy of association using an empirical method previously proposed to identify biological units in crystal structures. We investigate the effect on capsid formation of seven mutations, for which it has been experimentally assessed whether they disrupt capsid formation or not. With one exception, our approach predicts the effect of the mutations on the capsid stability. The method allows the identification of interaction networks, which drive capsid assembly, and highlights the plasticity of the interfaces between subunits in the capsid. Proteins 2015; 83:1733–1741. © 2015 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc
Investigation of quercetin‐induced HepG2 cell apoptosis‐associated cellular biophysical alterations by atomic force microscopy
Authors: Pi Jiang , Li Baole , Tu Lvying , Zhu Haiyan , Jin Hua , Yang Fen , Bai Haihua , Cai Huaihong , Cai Jiye
Published: July 2015

Quercetin, a wildly distributed bioflavonoid, has been proved to possess excellent antitumor activity on hepatocellular carcinoma (HCC). In the present study, the biophysical properties of HepG2 cells were qualitatively and quantitatively determined using high resolution atomic force microscopy (AFM) to understand the anticancer effects of quercetin on HCC cells at nanoscale. The results showed that quercetin could induce severe apoptosis in HepG2 cells through arrest of cell cycle and disruption of mitochondria membrane potential. Additionally, the nuclei and F‐actin structures of HepG2 cells were destroyed by quercetin treatment as well. AFM morphological data showed some typical apoptotic characterization of HepG2 cells with increased particle size and roughness in the ultrastructure of cell surface upon quercetin treatment. As an important biophysical property of cells, the membrane stiffness of HepG2 cells was further quantified by AFM force measurements, which indicated that HepG2 cells became much stiffer after quercetin treatment. These results collectively suggest that quercetin can be served as a potential therapeutic agent for HCC, which not only extends our understanding of the anticancer effects of quercetin against HCC cells into nanoscale, but also highlights the applications of AFM for the investigation of anticancer drugs. SCANNING 38:100–112, 2016. © 2015 Wiley Periodicals, Inc.
Design of intelligent KNN‐based alarm filter using knowledge‐based alert verification in intrusion detection
Authors: Meng Weizhi , Li Wenjuan , Kwok Lam‐For
Published: July 2015

Network intrusion detection systems (NIDSs) have been widely deployed in various network environments to defend against different kinds of network attacks. However, a large number of alarms especially unwanted alarms such as false alarms and non‐critical alarms could be generated during the detection, which can greatly decrease the efficiency of the detection and increase the burden of analysis. To address this issue, we advocate that constructing an alarm filter in terms of expert knowledge is a promising solution. In this paper, we develop a method of knowledge‐based alert verification and design an intelligent alarm filter based on a multi‐class k‐nearest‐neighbor classifier to filter out unwanted alarms. In particular, the alarm filter employs a rating mechanism by means of expert knowledge to classify incoming alarms to proper clusters for labeling. We further analyze the effect of different classifier settings on classification accuracy with two alarm datasets. In the evaluation, we investigate the performance of the alarm filter with a real dataset and in a network environment, respectively. Experimental results indicate that our alarm filter can effectively filter out a number of NIDS alarms and can achieve a better outcome under the advanced mode. Copyright © 2015 John Wiley & Sons, Ltd.
Single‐Particle Cryo‐EM and 3D Reconstruction of Hybrid Nanoparticles with Electron‐Dense Components
Authors: Yu Guimei , Yan Rui , Zhang Chuan , Mao Chengde , Jiang Wen
Published: July 2015

Single‐particle cryo‐electron microscopy (cryo‐EM), accompanied with 3D reconstruction, is a broadly applicable tool for the structural characterization of macromolecules and nanoparticles. Recently, the cryo‐EM field has pushed the limits of this technique to higher resolutions and samples of smaller molecular mass, however, some samples still present hurdles to this technique. Hybrid particles with electron‐dense components, which have been studied using single‐particle cryo‐EM yet with limited success in 3D reconstruction due to the interference caused by electron‐dense elements, constitute one group of such challenging samples. To process such hybrid particles, a masking method is developed in this work to adaptively remove pixels arising from electron‐dense portions in individual projection images while maintaining maximal biomass signals for subsequent 2D alignment, 3D reconstruction, and iterative refinements. As demonstrated by the success in 3D reconstruction of an octahedron DNA/gold hybrid particle, which has been previously published without a 3D reconstruction, the devised strategy that combines adaptive masking and standard single‐particle 3D reconstruction approach has overcome the hurdle of electron‐dense elements interference, and is generally applicable to cryo‐EM structural characterization of most, if not all, hybrid nanomaterials with electron‐dense components.
XRF study on the gilding technique of the fresco ‘Crocifissione con Santi’ by Beato Angelico in the San Marco monastery in Florence
Authors: Mazzinghi A. , Giuntini L. , Gelli N. , Ruberto C.
Published: July 2015

This study focused on the gildings of a famous Italian fresco, the Crocifissione con Santi by Beato Angelico, exploiting the XRF spectrometer developed at the LABEC laboratory. This can be considered the first scientific study on the gilding technique on frescoes of Beato Angelico. In order to characterise the original gilding technique and identify restored parts, more than 30 points were analysed in different areas of the wall painting, mostly in halos and decorations. In particular, the main goal was to verify whether Beato Angelico used the composite tin–gold foil, the most common gilding technique during the Italian Renaissance. This study allowed discriminating the original from the restored gildings, and to characterise the layers in both cases, by means of iron Kα/Kβ ratio. Copyright © 2015 John Wiley & Sons, Ltd.
Enhancing xylanase production in the thermophilic fungus Myceliophthora thermophila by homologous overexpression of Mtxyr1
Authors: Wang Juan , Wu Yaning , Gong Yanfen , Yu Shaowen , Liu Gang
Published: July 2015

The xylanase regulator 1 protein in Myceliophthora thermophila ATCC42464 (MtXyr1) is 60 % homologous with that of Trichoderma reesei. However, MtXyr1’s regulatory role on cellulolytic and xylanolytic genes in M. thermophila is unknown. Herein, MtXyr1 was overexpressed under the control of the MtPpdc (pyruvate decarboxylase) promoter. Compared with the wild type, the extracellular xylanase activities of the transformant cultured in non-inducing and inducing media for 120 h were 25.19- and 9.04-fold higher, respectively. The Mtxyr1 mRNA level was 300-fold higher than in the wild type in corncob-containing medium. However, the filter paper activity and endoglucanase activities were unchanged in corncob-containing medium and glucose-containing medium. The different zymograms between the transformant and the wild type were analyzed and identified by mass spectrometry as three xylanases of the glycoside hydrolase (GH) family 11. Thus, overexpression of xyr1 resulted in enhanced xylanase activity in M. thermophila. Xylanase production could be improved by overexpressing Mtxyr1 in M. thermophila.
Transcription factor IKZF1 is degraded during the apoptosis of multiple myeloma cells induced by kinase inhibition
Authors: Liu Yaobin , He Xian , Sui Yiyan , Yu Rong , Xu Guoqiang
Published: July 2015

Immunomodulatory drugs such as thalidomide, lenalidomide, and pomalidomide exhibit high responsive rates for newly identified or relapsed multiple myeloma patients. However, their mechanisms of action are not completely understood. One mechanism involves the ubiquitination and degradation of two transcription factors, IKZF1 and IKZF3. Whether there are other degradation pathways for IKZF1 in myeloma cells remains unknown. Here, we found that although IKZF1 ubiquitination was reduced, its stability was also significantly reduced in MM1.S and OPM2 cells treated with kinase inhibitors, 5,6‐dichlorobenzimidazole riboside (DRB) or roscovitine. Through pharmacological inhibition and biochemical approaches we demonstrated that instead of undergoing the ubiquitin–proteasome pathway, IKZF1 was degraded through apoptosis induced by kinase inhibition. This result may provide a new direction in developing therapeutic treatments for myeloma patients.
Homodimerization of glucocorticoid receptor from single cells investigated using fluorescence correlation spectroscopy and microwells
Authors: Oasa Sho , Sasaki Akira , Yamamoto Johtaro , Mikuni Shintaro , Kinjo Masataka
Published: July 2015

Glucocorticoid receptor α (GR) binds to the promoter regions of target genes as a homodimer and activates its transcriptional process. Though the homodimerization is thought to be the initial and essential process, the dissociation constant for homodimerization of GR remains controversial. To quantify homodimerization of (enhanced green fluorescence protein) EGFP–(glucocorticoid receptor) GR, the particle brightness in lysates from single cell was estimated for the fraction of homodimeric EGFP–GR using fluorescence correlation spectroscopy and microwells. Fitting the data with a bimolecular reaction model, the dissociation constant was determined. Moreover slow‐diffusion complex was observed. These results suggest that EGFP–GR forms not only a monomer–dimer equivalent state but also a large‐molecular‐weight complex.
Identifying the true origin of sustained monomorphic ventricular tachycardia associated with dilated‐phase hypertrophic cardiomyopathy: A case of successful catheter ablation
Authors: Kawakami Hiroshi , Nagai Takayuki , Fujii Akira , Uetani Teruyoshi , Nishimura Kazuhisa , Inoue Katsuji , Suzuki Jun , Satomi Kazuhiro , Okura Takafumi , Higaki Jitsuo , Ogimoto Akiyoshi
Published: July 2015

This case report describes sustained monomorphic ventricular tachycardia (VT) caused by a large epicardial scar, related to dilated‐phase hypertrophic cardiomyopathy mimicking VT originating from the apical septum. VT resolved with epicardial catheter ablation. The exit of the VT circuit suggested that a 12‐lead electrocardiogram can be remote with respect to the critical isthmus in this case. In patients with structural heart disease, it is difficult to identify the VT reentrant circuit by surface electrocardiography, which shows only the exit site. VT originating in the epicardium should be considered, even if the suspected origin is another ventricular site.
Implementation of a volunteer university student research assistant program in an emergency department: the nuts and bolts for success
Authors: Steadman Patrick E. , Crudden Johanna , Boutis Kathy
Published: July 2015

Prospective research studies often advance clinical practice in the emergency department (ED), but they can be costly and difficult to perform. In this report, we describe the implementation of a volunteer university student research assistant program that provides students exposure to medicine and clinical research while simultaneously increasing the capacity of an ED’s research program. This type of program provides 15 hours per day of research assistant coverage for patient screening and enrolment for minimal risk research studies, and screening for higher risk studies. The latter is true without the added burden or costs of co-administering university course credit or pay for service, which are common features of most of these types of programs currently in operation. We have shown that our volunteer-based program is effective for an ED’s research success as well as for its student participants. For other EDs interested in adopting similar programs, we provide the details on how to get such a program started and highlight the structure and non-monetary incentives that facilitate a program’s ongoing success.
The impact of prehospital resuscitation research on in-hospital care
Authors: Mausz Justin , Cheskes Sheldon
Published: July 2015

Since their introduction over 40 years ago, paramedics have been trained to deliver select advanced life support interventions in the community with the goal of reducing morbidity and mortality from cardiovascular disease and trauma. The ensuing decades witnessed a great deal of interest in paramedic care, with an exponential growth in prehospital resuscitation research. As part of theCJEMseries on emergency medical services (EMS), we review recent prehospital research in out-of-hospital cardiac arrest and discuss how, in a novel departure from the origins of EMS, prehospital research is beginning to influence in-hospital care. We discuss emerging areas of study related to cardiopulmonary resuscitation (CPR) quality, therapeutic hypothermia, termination of resuscitation, and the use of end-tidal carbon dioxide measurement, as well as the subtle ripple effects that prehospital research is having on the broader understanding of the management of these critically ill patients.
Systematic Consensus Building on Disaster Mental Health Services After the Great East Japan Earthquake by Phase
Authors: Fukasawa Maiko , Suzuki Yuriko , Nakajima Satomi , Asano Keiko , Narisawa Tomomi , Kim Yoshiharu
Published: July 2015

Objective

We intended to build consensus on appropriate disaster mental health services among professionals working in the area affected by the Great East Japan Earthquake.

Methods

We focused on the first 3 months after the disaster, divided into 3 phases: immediate aftermath, acute phase, and midphase. We adopted the Delphi process and asked our survey participants (n=115) to rate the appropriateness of specific mental health services in each phase and comment on them. We repeated this process 3 times, giving participants feedback on the results of the previous round. Through this process, we determined the criterion for positive consensus for each item as having the agreement of more than 80% of the participants.

Results

We found that the importance of acute psychiatric care and prescribing regular medication for psychiatric patients gained positive consensus in the immediate aftermath and acute phase. Counseling and psychoeducation after traumatic events or provision of information gained consensus in the acute phase and midphase, and screening of mental distress gained consensus in the midphase.

Conclusions

Higher priority was given to continuous psychiatric services in the immediate aftermath and mental health activities in later phases. (Disaster Med Public Health Preparedness. 2015;9:359–366)
Avoiding Negligence and Profusion: The Failure of the Joint-Stock Form in the Anglo-Indian Tea Trade, 1840–1870
Authors: ALDOUS MICHAEL
Published: July 2015

In the nineteenth century, firms operating in the Anglo-Indian tea trade were organized using a variety of ownership forms, including partnership, joint-stock, and a combination of the two, known as the managing agency. Faced with both an increasing need for fixed capital and high agency costs caused by the distance between owners and managers, the firms adapted and increasingly adopted the hybrid managing agency model to overcome these problems. Using new data from Calcutta and Bengal Commercial Registers and detailed case studies of the Assam Company and Gillanders, Arbuthnot and Co., this article demonstrates that British entrepreneurs did not see the choice of ownership as a dichotomy or firm boundaries as fixed, but instead drew innovatively on the strengths of different forms of ownership to compete and grow successfully.
Joint ergodicity along generalized linear functions
Authors: BERGELSON V. , LEIBMAN A. , SON Y.
Published: July 2015

A criterion of joint ergodicity of several sequences of transformations of a probability measure space $X$ of the form $T_{i}^{\unicode[STIX]{x1D711}_{i}(n)}$ is given for the case where $T_{i}$ are commuting measure-preserving transformations of $X$ and $\unicode[STIX]{x1D711}_{i}$ are integer-valued generalized linear functions, that is, the functions formed from conventional linear functions by an iterated use of addition, multiplication by constants, and the greatest integer function. We also establish a similar criterion for joint ergodicity of families of transformations depending on a continuous parameter, as well as a condition of joint ergodicity of sequences $T_{i}^{\unicode[STIX]{x1D711}_{i}(n)}$ along primes.
Measurable rigidity for Kleinian groups
Authors: JEON WOOJIN , OHSHIKA KEN’ICHI
Published: July 2015

Let$G,H$be two Kleinian groups with homeomorphic quotients$\mathbb{H}^{3}/G$and$\mathbb{H}^{3}/H$. We assume that$G$is of divergence type, and consider the Patterson–Sullivan measures of$G$and$H$. The measurable rigidity theorem by Sullivan and Tukia says that a measurable and essentially directly measurable equivariant boundary map$\widehat{k}$from the limit set$\unicode[STIX]{x1D6EC}_{G}$of$G$to that of$H$is either the restriction of a Möbius transformation or totally singular. In this paper, we shall show that such$\widehat{k}$always exists. In fact, we shall construct$\widehat{k}$concretely from the Cannon–Thurston maps of$G$and$H$.
Stable sets and mean Li–Yorke chaos in positive entropy actions of bi-orderable amenable groups
Authors: HUANG WEN , JIN LEI
Published: July 2015

It is proved that positive entropy implies mean Li–Yorke chaos for a$G$-system, where$G$is a countable, infinite, discrete, bi-orderable amenable group. Examples are given for the cases of integer lattice groups and groups of integer unipotent upper triangular matrices.
Executive function and attention-deficit/hyperactivity disorder in Ugandan children with perinatal HIV exposure
Authors: Burkey M. D. , Murray S. M. , Bangirana P. , Familiar I. , Opoka R. O. , Nakasujja N. , Boivin M. , Bass J.K.
Published: July 2015

Background.

Attention-deficit/hyperactivity disorder (ADHD) is among the most commonly diagnosed mental disorders in childhood and is associated with substantial deficits in executive functioning and lost academic and occupational attainment. This study evaluates symptoms of ADHD and their association with neurocognitive deficits in a cohort of rural Ugandan children who were born to HIV-infected mothers.

Methods.

We assessed ADHD symptoms and executive function (including memory and attention) in a non-clinical sample of children born to HIV-infected mothers in rural eastern Uganda. Analyses included assessments of the psychometric properties, factor structure, and convergent and discriminant validity of the ADHD measure (ADHD-Rating Scale-IV); and executive function deficits in children meeting symptom criteria for ADHD.

Results.

232 children [54% female; mean age 7.8 years (s.d.2.0)] were assessed for ADHD and executive function deficits. The ADHD measure showed good internal consistency (α = 0.85.) Confirmatory factor analysis showed an acceptable fit for the diagnostic and statistical manual of mental disorders (DSM-5) two-factor model. Subjects meeting DSM-5 symptom criteria for ADHD had worse parent-rated executive function on six out of seven subscales.

Conclusions.

Our results demonstrate structural validity of the ADHD measure with this population, strong associations between ADHD symptom severity and poorer executive function, and higher levels of executive function problems in perinatally HIV-exposed Ugandan children with ADHD. These findings suggest that ADHD may be an important neurocognitive disorder associated with executive function problems among children in sub-Saharan African settings where perinatal HIV exposure is common.
Impact of the Centers for Medicare and Medicaid Services Hospital-Acquired Conditions Policy on Billing Rates for 2 Targeted Healthcare-Associated Infections
Authors: Kawai Alison Tse , Calderwood Michael S. , Jin Robert , Soumerai Stephen B. , Vaz Louise E. , Goldmann Donald , Lee Grace M.
Published: July 2015

BACKGROUND

The 2008 Centers for Medicare & Medicaid Services hospital-acquired conditions policy limited additional payment for conditions deemed reasonably preventable.

OBJECTIVE

To examine whether this policy was associated with decreases in billing rates for 2 targeted conditions, vascular catheter-associated infections (VCAI) and catheter-associated urinary tract infections (CAUTI).

STUDY POPULATION

Adult Medicare patients admitted to 569 acute care hospitals in California, Massachusetts, or New York and subject to the policy.

DESIGN

We used an interrupted times series design to assess whether the hospital-acquired conditions policy was associated with changes in billing rates for VCAI and CAUTI.

RESULTS

Before the policy, billing rates for VCAI and CAUTI were increasing (prepolicy odds ratio per quarter for VCAI, 1.17 [95% CI, 1.11–1.23]; for CAUTI, 1.19 [1.16–1.23]). The policy was associated with an immediate drop in billing rates for VCAI and CAUTI (odds ratio for change at policy implementation for VCAI, 0.75 [95% CI, 0.69–0.81]; for CAUTI, 0.87 [0.79–0.96]). In the postpolicy period, we observed a decreasing trend in the billing rate for VCAI and a leveling-off in the billing rate for CAUTI (postpolicy odds ratio per quarter for VCAI, 0.98 [95% CI, 0.97–0.99]; for CAUTI, 0.99 [0.97–1.00]).

CONCLUSIONS

The Centers for Medicare & Medicaid Services hospital-acquired conditions policy appears to have been associated with immediate reductions in billing rates for VCAI and CAUTI, followed by a slight decreasing trend or leveling-off in rates. These billing rates, however, may not correlate with changes in clinically meaningful patient outcomes and may reflect changes in coding practices.

Infect. Control Hosp. Epidemiol. 2015;36(8):871–877
Dispersion in two-dimensional turbulent buoyant plumes
Authors: Rocco Stefano , Woods Andrew W.
Published: July 2015

Using high-resolution imaging and dye studies, we investigate experimentally the mixing of a tracer by the eddies within a two-dimensional turbulent buoyant plume. Instantaneously, the plume consists of a series of eddies, and at each point along the centreline of the plume, the along-plume speed of the leading edge of the eddies $w_{e}\approx 1.3f^{1/3}$, where $f$ is the buoyancy flux, while the product of the length scale, $A$, and frequency, ${\it\omega}$, of the eddies ${\it\omega}A\approx 0.15f^{1/3}$. The circulation and flow associated with the eddies lead to longitudinal mixing relative to the mean flow. To illustrate this mixing, we analyse the evolution of the horizontally averaged dye front produced by adding a constant flux of dye to a steady plume for times $t>0$. We show that the centre of mass of the horizontally averaged dye front has an along-plume speed ${\approx}1.04f^{1/3}$. This is consistent with the predictions of a time-averaged model for the evolution of the horizontally averaged mass, momentum and buoyancy flux in the plume. The new data also show that the longitudinal spreading of the horizontally averaged dye front can be described in terms of a dispersivity ${\approx}\,0.02f^{1/3}z$, where $z$ is the vertical distance below the source. This model of longitudinal mixing enables calculation of the residence time distribution of material in the plume, which may be key to modelling the products of a reaction in which the reaction time is comparable to the travel time in the plume.
Buoyancy instability of homologous implosions
Authors: Johnson B. M.
Published: July 2015

I consider the hydrodynamic stability of imploding ideal gases as an idealized model for inertial confinement fusion capsules, sonoluminescent bubbles and the gravitational collapse of astrophysical gases. For oblate modes (short-wavelength incompressive modes elongated in the direction of the mean flow), a second-order ordinary differential equation is derived that can be used to assess the stability of any time-dependent flow with planar, cylindrical or spherical symmetry. Upon further restricting the analysis to homologous flows, it is shown that a monatomic gas is governed by the Schwarzschild criterion for buoyant stability. Under buoyantly unstable conditions, both entropy and vorticity fluctuations experience power-law growth in time, with a growth rate that depends upon mean flow gradients and, in the absence of dissipative effects, is independent of mode number. If the flow accelerates throughout the implosion, oblate modes amplify by a factor$(2C)^{|N_{0}|t_{i}}$, where$C$is the convergence ratio of the implosion,$N_{0}$is the initial buoyancy frequency and$t_{i}$is the implosion time scale. If, instead, the implosion consists of a coasting phase followed by stagnation, oblate modes amplify by a factor$\exp ({\rm\pi}|N_{0}|t_{s})$, where$N_{0}$is the buoyancy frequency at stagnation and$t_{s}$is the stagnation time scale. Even under stable conditions, vorticity fluctuations grow due to the conservation of angular momentum as the gas is compressed. For non-monatomic gases, this additional growth due to compression results in weak oscillatory growth under conditions that would otherwise be buoyantly stable; this over-stability is consistent with the conservation of wave action in the fluid frame. The above analytical results are verified by evolving the complete set of linear equations as an initial value problem, and it is demonstrated that oblate modes are the fastest-growing modes and that high mode numbers are required to reach this limit (Legendre mode$\ell \gtrsim 100$for spherical flows). Finally, comparisons are made with a Lagrangian hydrodynamics code, and it is found that a numerical resolution of${\sim}30$zones per wavelength is required to capture these solutions accurately. This translates to an angular resolution of${\sim}(12/\ell )^{\circ }$, or${\lesssim}0.1^{\circ }$to resolve the fastest-growing modes.
Bouncing on thin air: how squeeze forces in the air film during non-wetting droplet bouncing lead to momentum transfer and dissipation
Authors: de Ruiter Jolet , Lagraauw Rudy , Mugele Frieder , van den Ende Dirk
Published: July 2015

Millimetre-sized droplets are able to bounce multiple times on flat solid substrates irrespective of their wettability, provided that a micrometre-thick air layer is sustained below the droplet, limiting $\mathit{We}$ to ${\lesssim}4$. We study the energy conversion during a bounce series by analysing the droplet motion and its shape (decomposed into eigenmodes). Internal modes are excited during the bounce, yet the viscous dissipation associated with the in-flight oscillations accounts for less than 20 % of the total energy loss. This suggests a significant contribution from the bouncing process itself, despite the continuous presence of a lubricating air film below the droplet. To study the role of this air film we visualize it using reflection interference microscopy. We quantify its thickness (typically a few micrometres) with sub-millisecond time resolution and ${\sim}30~\text{nm}$ height resolution. Our measurements reveal strong asymmetry in the air film shape between the spreading and receding phases of the bouncing process. This asymmetry is crucial for effective momentum reversal of the droplet: lubrication theory shows that the dissipative force is repulsive throughout each bounce, even near lift-off, which leads to a high restitution coefficient. After multiple bounces the droplet eventually hovers on the air film, while continuously experiencing a lift force to sustain its weight. Only after a long time does the droplet finally wet the substrate. The observed bounce mechanism can be described with a single oscillation mode model that successfully captures the asymmetry of the air film evolution.
The Economic-Social Duality for Executive Rationale: The Interplay between Resource Pool and Game Rule for Sense-Giving and Sense-Making
Authors: Li Peter Ping
Published: July 2015

I truly enjoyed reading the perspective article entitled ‘Advancing indigenous management theory: Executive rationale as an institutional logic’ by Gordon Redding and Michael Witt (2015), especially its implications for a ‘promising avenue for indigenous management research’ (179). I agree with the authors in general terms that the research on the impact of culture as an informal institution, and also the effect of formal institutions, on business practices must come down from a highly abstract level to a more pragmatic ground, especially their interaction and integration as embodied by various specific mechanisms to guide practices. For that purpose, Redding and Witt introduce an interesting notion of ‘executive rationale’ to guide action. Applying the abstract notion of institutional logic to specific business practices,executive rationalerefers to the ‘socially constructed, historical patterns of material practices, assumptions, values, beliefs, and rules by which individuals produce and reproduce their material subsistence, organize time and space, and provide meaning to their social reality’ (Thornton & Ocasio, 2008: 101) in the specific context of business practices. In other words, executive rationale provides a mental blueprint for practical actions in a business context. In addition, the authors have empirically generated a tentative model with multiple dimensions to compare the dominant executive rationales as institutionally-embedded across five key economies.
The Global Corporate Organization
Authors: Pope Shawn , Meyer John W.
Published: July 2015

I feel very fortunate to be able to open the MOR Dialogue, Debate, and Discussion editorial section with a striking perspective advanced by Shawn Pope and John W. Meyer of Stanford University. They point to the rise of a global corporate organization that is shedding its national distinctiveness and any remaining local rooting. Instead, they envision global standardization as no longer related to national origins and as managed according to abstract, universalistic principles. The global standard is furthermore run by managers who graduated from the same homogenous business programs, who gain advice from like-minded consultants, and who, of course, go to the same Davos meetings. The new standard, the universal corporation, seeks to convey its socially responsible character by confirming, sometimes voluntarily, to the standards of excellence as decreed by other organizations perhaps increasingly like itself. This provocative perspective invites debate – refutations and support alike – in future MOR issues and blogs. Where does your research lead you to take a stand?
THE ANCESTRY OF NERVA
Authors: Hillard T.W. , Beness J.L.
Published: July 2015

It will be noticed that, in the stemma above, no line of descent is marked from the first generation registered therein to the following generations. The genealogy of the Emperor Nerva is customarily traced back to the consul of 36 b.c., M. Cocceius Nerva (above, right). This short note will underline the ancient testimony found amongst the Pseudacroniana tracing his descent from the latter's brother, the consummate diplomat (above, left). There are ramifications. Amongst the items of interest will be the light shone upon what Dio and Eutropius (and/or their sources) understood to be Nerva's standing at the time of his accession. Before passing on to Pseudacron's datum, it might be worthwhile pausing on that point, as well as briefly contemplating the factors that actually bore upon the emperor's ancestral training.
The Grasshopper’s Error: Or, On How Life is a Game
Authors: KOLERS AVERY
Published: July 2015

I here defend the thesis that the best life is the life that one plays as a game—specifically, a ‘Suitsian’ game that meets the definition proposed inThe Grasshopperby Bernard Suits. Even more specifically, it is a nested, open, role-playing game where the life’s quality as a game partly depends on there being no more people than players. To defend this thesis I refute two powerful challenges to it, one from Thomas Hurka (2006) and another from withinThe Grasshopperitself. In the process, I offer a new interpretation of that enigmatic and challenging book.
THE EFFECT OF PREGNANCY SPACING ON FETAL SURVIVAL AND NEONATAL MORTALITY IN RWANDA: A HECKMAN SELECTION ANALYSIS
Authors: Habimana-Kabano Ignace , Broekhuis Annelet , Hooimeijer Pieter
Published: July 2015

Most studies on birth intervals and infant mortality ignore pregnancies that do not result in live births. Yet, fetal deaths are important in infant mortality analyses for three reasons: ignoring fetal deaths between two live births lengthens the measured interval between births, implying that short intervals are underestimated; the recommended inter-pregnancy interval (IPI) after a fetal loss is shorter (6 months) than after a live birth (24 months), as the effect of IPI on outcomes might differ according to the previous type of pregnancy outcome; fetal death will selectively reduce the population at risk of neonatal mortality, leading to biased results. This study uses the Heckman selection model to simultaneously estimate the combined effect of IPI duration and the type of pregnancy outcome at the start of the interval on pregnancy survival and neonatal mortality. The analysis is based on retrospective data from the Rwanda Demographic Health Surveys of 2000, 2005 and 2010. The results show a significant selection effect. After controlling for the selection bias, short (<6 months) and long (>60 months) intervals after a fetal death reduce the chances of pregnancy survival, but no longer have an effect on neonatal mortality. For intervals starting with a live birth, the reverse is true. Short intervals (<24 months) do not affect pregnancy survival but increase the odds of neonatal mortality. If the previous child died in infancy, the highest odds are found for neonatal death regardless of the IPI duration.
Trajectories of childhood neighbourhood cohesion and adolescent mental health: evidence from a national Canadian cohort
Authors: Kingsbury M. , Kirkbride J. B. , McMartin S. E. , Wickham M. E. , Weeks M. , Colman I.
Published: July 2015

Background

The objective of this study was to examine associations between trajectories of childhood neighbourhood social cohesion and adolescent mental health and behaviour.

Method

This study used data from the National Longitudinal Survey of Children and Youth, a nationally representative sample of Canadian children. The sample included 5577 children aged 0–3 years in 1994–1995, prospectively followed until age 12–15 years. Parental perceived neighbourhood cohesion was assessed every 2 years. Latent growth class modelling was used to identify trajectories of neighbourhood cohesion. Mental health and behavioural outcomes were self-reported at age 12–15 years. Logistic regression was used to examine associations between neighbourhood cohesion trajectories and outcomes, adjusting for potential confounders.

Results

Five distinct trajectories were identified: ‘stable low’ (4.2%); ‘moderate increasing’ (9.1%); ‘stable moderate’ (68.5%); ‘high falling’ (8.9%); and ‘stable high’ (9.3%). Relative to those living in stable moderately cohesive neighbourhoods, those in stable low cohesive neighbourhoods were more likely to experience symptoms of anxiety/depression [odds ratio (OR) = 1.73, 95% confidence interval (CI) 1.04–2.90] and engage in indirect aggression (OR = 1.62, 95% CI 1.07–2.45). Those with improvements in neighbourhood cohesion had significantly lower odds of hyperactivity (OR = 0.67, 95% CI 0.46–0.98) and indirect aggression (OR = 0.69, 95% CI 0.49–0.96). In contrast, those with a decline in neighbourhood cohesion had increased odds of hyperactivity (OR = 1.67, 95% CI 1.21–2.29). Those in highly cohesive neighbourhoods in early childhood were more likely to engage in prosocial behaviour (‘high falling’: OR = 1.93, 95% CI 1.38–2.69; ‘stable high’: OR = 1.89, 95% CI 1.35–2.63).

Conclusions

These results suggest that neighbourhood cohesion in childhood may have time-sensitive effects on several domains of adolescent mental health and behaviour.
Arguing with the Heathens: The Further Reformation and the Ethnohistory of Johannes Hoornbeeck (1617–1666)
Authors: Gommans Jos , Loots Ineke
Published: July 2015

Johannes Hoornbeeck (1617–1666) was a Dutch Protestant theologian, generally regarded as a member of the so-called Further Reformation in the Netherlands. He wrote a number of theological works in Latin and in Dutch. Most of his works have a polemical character, defending his orthodox protestant stance against a variety of heretical views. InDe conversione Indorum et gentilium, based on disputations with students and published posthumously, he enters into a discussion with the ‘heathens’. To this end he carefully combines biblical and classical scholarship and also reflects on the latest ethnographical information collected by both Protestant and Catholic travellers and missionaries. The book is characterised by great erudition and by an openness for other people’s opinions that necessitates the constant appraisal of one’s own point of view. We argue that such an open engagement with heretical views ultimately carries the danger of a sceptical view of one’s own religion.
Belonging in Africa: Frederik Svane and Christian Protten on the Gold Coast in the Eighteenth Century
Authors: Simonsen Gunvor
Published: July 2015

The idea that the African Atlantic world was populated by Atlantic Creoles who crossed cultural divides with relative ease is appealing, and it lends itself well to studies of identity formation that highlight the talents and opportunities that emerged from processes of cultural blending. Yet an examination of how travelling Africans ascribed meaning to their spatial and emotional groundings underlines that creolization in the African Atlantic was less smooth than suggested by the figure of the Atlantic Creole. For Frederik Svane and Christian Protten, two Euro-African men born on the Gold Coast in the early eighteenth century, Creole conditions resulted in identity practices that ranged from the complete rejection of African culture to a celebration and redefinition of the significance of African origins in the Atlantic world.
Calamitous Voyages: the social space of shipwreck and mutiny narratives in the Dutch East India Company
Authors: Guy Richard
Published: July 2015

This article analyses four accounts of mutinies and wrecks of Dutch East India Company ships: those of theNieuw Hoorn, Batavia, BlydorpandNijenburg. These stories can be read as worst-case survival manuals, which support the Company’s discourse of discipline. They advise readers that the best option in the event of disaster is to obey the officers’ orders and the Company’s rules, linking this advice to moral and religious ideas of endurance and divine providence that were common in the Dutch Republic in the seventeenth and eighteenth century. The accounts also link shipboard spatial protocols with proper social order. The stories present the Indies as a dangerous physical and moral testing ground, from which the ship provides a vital protective barrier, but only if the crew acts with disciplined solidarity and shows seamanlike virtues of cohesion and perseverance. Disorder among the crew, especially the breaching of spatial boundaries between officers and men, invites the dangers of the Indies to penetrate the safe space of the ship. Such breaches threaten all the boundaries on which the lives of the ship and crew depend: between the ship and the sea, between moral and immoral behaviour, and between Europeans and the non-European world. Where spatial boundaries break down, the stories show chaos and calamity following. Where the stories have ‘happy endings’, these are brought about by the re-establishment of proper spatial and social hierarchies.
CARTAS ESPAÑOLAS DE JEAN-BAPTISTE SAY: EVIDENCIAS PARA EL ESTUDIO DE LA CIRCULACIÓN DE IDEAS ECONÓMICAS
Authors: Menudo José M.
Published: July 2015

This paper transcribes and annotates five unpublished letters that Manuel María Gutiérrez, Álvaro Flórez Estrada and the Marquis of Valle Santoro respectively sent to Jean-Baptiste Say. An initial hypothesis holds the importance of this correspondence in order to argue the connection of the Spanish authors with the canonical works. We focus on several questions related to the transmission of economic ideas. First, the translation of Say’s work is a collective project structured around the Real Sociedad Económica de Amigos del País de Madrid. Secondly, we explain how the translator expurgates the condemnable passages in order to publish Say’sTraité d`économie politiquein Spanish, those connected to the influence of religion on economic development and public education to be exact.
The unified transform for the heat equation: II. Non-separable boundary conditions in two dimensions
Authors: MANTZAVINOS D. , FOKAS A. S.
Published: July 2015

We use the two-dimensional heat equation as an illustrative example to show that the unified transform is capable of constructing analytical solutions for linear evolution partial differential equations (PDEs) in two spatial dimensions involving non-separable boundary conditions. Such non-separable boundary value problems apparently cannot be solved by the usual transforms. We note that the unified transform always yields integral expressions which, in contrast to the expressions obtained by the usual transforms, have the advantage that are uniformly convergent at the boundary. Thus, even for the cases of separable boundary value problems where the usual transforms can be implemented, the unified transform provides alternative solution expressions which have advantages for both numerical and asymptotic considerations. The former advantage is illustrated by providing the numerical evaluation of a typical boundary value problem, by extending the approach of Flyer and Fokas (2008Proc. R. Soc.464, 1823–1849). This work is the two-dimensional continuation of the heat equation with oblique Robin boundary conditions which was analysed in Mantzavinos and Fokas (2013Eur. J. Appl. Math.24(6), 857–886.
The large-time asymptotic solution of the mKdV equation
Authors: LEACH J. A. , BASSOM ANDREW P.
Published: July 2015

In this paper, an initial-value problem for the modified Korteweg-de Vries (mKdV) equation is addressed. Previous numerical simulations of the solution of

\[
u_{t} - 6u^{2} u_{x}+u_{xxx}=0, \quad -\infty<x<\infty, \quad t>0,
\]

where x and t represent dimensionless distance and time respectively, have considered the evolution when the initial data is given by

\[
u(x,0)=\tanh ( Cx ), \quad -\infty<x<\infty,
\]

for C constant. These computations suggest that kink and soliton structures develop from this initial profile and here the method of matched asymptotic coordinate expansions is used to obtain the complete large-time structure of the solution in the particular case C = 1/3. The technique is able to confirm some of the numerical predictions, but also forms a basis that could be easily extended to account for other initial conditions and other physically significant equations. Not only can the details of the relevant long-time structure be determined but rates of convergence of the solution of the initial-value problem be predicted.