bluuebunny/crossref_metadata_2025 huggingface dataset:
Certain Characterizations of Exponential and Geometric Distributions
Authors: Fosam E. B. , Shanbhag D. N.
Published: December 2018

It is revealed in particular that a characterization result that is much stronger than that given recently by Liang and Balakrishnan follows as a simple corollary of a known published result.
Completely Randomized Designs for Comparing Dual with Single Treatments
Authors: Gerami A. , Lewis S. M.
Published: December 2018

This paper considers n × m completely randomized factorial experiments in which one treatment combination, labelled 00, is excluded. The aim of the experiments is to compare the effects of having both factors at non-zero labelled levels with the effects of having only one factor at a non-zero labelled level. A necessary and sufficient condition is given for an A-optimal allocation of units to treatments, and a series of equireplicate, A-optimal designs is derived.
On Estimating Linear Relationships When Both Variables are Subject to Errors
Authors: Cheng Chi-Lun , Van Ness John W.
Published: December 2018

This paper discusses the problem of estimating a linear relationship between two variables observed with errors. It focuses on confidence intervals for the slope parameter and confidence regions for the intercept and slope parameters in Gaussian models. A compendium of existing results as well as new results are presented.
Frequentist and Bayesian Bartlett Correction of Test Statistics Based on Adjusted Profile Likelihoods
Authors: Diciccio Thomas J. , Stern Steven E.
Published: December 2018

For inference about a multidimensional parameter ψ in the presence of nuisance parameters, the usual log-profile-likelihood function M(ψ) is often replaced by an objective function M̄(ψ) = M(ψ) + B(ψ), where B(ψ) is Op(1). It is shown in this paper that under mild conditions on the adjustment function B(ψ) both frequentist and Bayesian Bartlett correction are possible for the adjusted likelihood ratio statistic arising from M̄(ψ). General formulae for the Bartlett adjustment factors are developed, and these formulae are evaluated for some specific adjustment functions B(ψ). Furthermore, conditions under which the frequentist and Bayesian adjustment factors agree to order Op(n  –3/2) are considered. In particular, prior probability density functions for which the highest posterior density region of posterior probability content 1 – α has frequentist coverage level 1 – α + O(n  –2) are characterized, and similar characterizations are given for likelihood-based regions.
Neural Networks and Related Methods for Classification
Authors: Ripley B. D.
Published: December 2018

Feed-forward neural networks are now widely used in classification problems, whereas non-linear methods of discrimination developed in the statistical field are much less widely known. A general framework for classification is set up within which methods from statistics, neural networks, pattern recognition and machine learning can be compared. Neural networks emerge as one of a class of flexible non-linear regression methods which can be used to classify via regression. Many interesting issues remain, including parameter estimation, the assessment of the classifiers and in algorithm development.
Estimation in the Mean Residual Life Regression Model
Authors: Maguluri Gangaji , Zhang Cun-Hui
Published: December 2018

The proportional mean residual life model was originally proposed by Oakes and Dasu. This model can be extended to a regression model with explanatory variables. We consider the problem of estimation of the regression parameter in this general model. We investigate two types of estimator, of which one is based on the maximum likelihood equation of the exponential regression model, and the other is based on the underlying proportional hazards structure of the model and Cox's estimating equation. We show that these estimators are consistent and asymptotically normal. We compare their performance by simulations.
Estimation and Tests of Fit for the Three-Parameter Weibull Distribution
Authors: Lockhart Richard A. , Stephens Michael A.
Published: December 2018

Estimation techniques are given for the three-parameter Weibull distribution, with all parameters unknown. Tables are given for the empirical distribution function statistics W  2, U  2 and A  2, for testing for the distribution.
Bayesian Model Discrimination and Bayes Factors for Linear Gaussian State Space Models
Authors: Frühwirth-Schnatter Sylvia
Published: December 2018

It is shown how to discriminate between different linear Gaussian state space models for a given time series by means of a Bayesian approach which chooses the model that minimizes the expected loss. A practical implementation of this procedure requires a fully Bayesian analysis for both the state vector and the unknown hyperparameters and is carried out by Markov chain Monte Carlo methods. An application to some non-standard situations such as testing hypotheses on the boundary of the parameter space, discriminating non-nested models and discrimination of more than two models is discussed in detail.
Predictive Model Selection
Authors: Laud Purushottam W. , Ibrahim Joseph G.
Published: December 2018

We consider the problem of selecting one model from a large class of plausible models. A predictive Bayesian viewpoint is advocated to avoid the specification of prior probabilities for the candidate models and the detailed interpretation of the parameters in each model. Using criteria derived from a certain predictive density and a prior specification that emphasizes the observables, we implement the proposed methodology for three common problems arising in normal linear models: variable subset selection, selection of a transformation of predictor variables and estimation of a parametric variance function. Interpretation of the relative magnitudes of the criterion values for various models is facilitated by a calibration of the criteria. Relationships between the proposed criteria and other well-known criteria are examined.
On the Influence Functions of Certain Bivariate Medians
Authors: Niinimaa A. , Oja H.
Published: December 2018

The asymptotic efficiency, influence function and breakdown properties of the multivariate median proposed by Oja are investigated and comparisons are made with two other generalizations of the median: the spatial median and the vector of marginal medians. It is shown that, for distributions with finite expectations, the Oja median has a bounded influence function although this median has 0% breakdown. For circular distributions, the influence functions of the Oja median and the spatial median coincide. The Oja median is then as efficient as the spatial median in the circular case but strictly better for any other elliptical case. It is noteworthy that the spatial median, however, has the best possible 50% breakdown. This phenomenon is analysed in the paper: it is shown that the finite sample breakdown point of the Oja median depends on the dispersion of the corrupted observations.
A Geometric Approach to Optimal Design for One-Parameter Non-Linear Models
Authors: Haines Linda M.
Published: December 2018

A geometric framework for constructing optimal Bayesian designs and maximin designs for non-linear models with a single unknown parameter and a prior distribution on that parameter, which is restricted in that it comprises exactly two points of support, is presented. The approach is illustrated by means of selected examples involving logistic regression and the simple exponential model, and its applicability to the construction of optimal designs for models with uncontrolled variation and to model robust designs is also demonstrated. In addition, the method is shown to provide some valuable insights into the general properties of optimal Bayesian designs for non-linear models.
A Class of Bayesian Models for Optimal Exploration
Authors: Glazebrook K. D. , Boys R. J.
Published: December 2018

Each of several locations contains an unknown number of objects of value. A single search of a location will discover some of these objects which are then removed. Discoveries yield rewards. A ‘distribution of effort’ problem is posed concerning how to explore the locations optimally—i.e. to maximize the expected return from discoveries made. This is formulated as a Bayes sequential decision problem for which index policies are optimal. A natural simple case is one in which, conditionally on the number of undiscovered objects at a location N, the number of discoveries made in a single search is binomial B(N, p) where p is a detection rate. For this case, we can gain considerable insight into how model structure relates to policy structure. The tail behaviour of the priors for the number of objects at each location plays an important role.
The Empirical Process Approach for Semiparametric Two-Sample Models with Heterogeneous Treatment Effect
Authors: Hsieh Fushing
Published: December 2018

Two types of semiparametric model are proposed for comparing two samples with possibly heterogeneous treatment effects. One model is a two-sample location-scale model which assumes that the Q-Q-plot of the two distributions involved is linear; the other is the class of two-sample transformation models which assume parametric forms for a probability plot—the receiver operating characteristic curve. The empirical process approach is used to construct strong approximations for the empirical curves of both types of plot and a convenient generalized least squares (GLS) estimator is derived. The approximate finite sample precision of the estimators can be easily evaluated. Asymptotically, the GLS estimator is shown to be efficient for the first model. A difficulty involved in developing the theory of asymptotic efficiency is discussed for the transformation models. The GLS estimator is shown numerically to approach the Fisher information bound for the proportional hazards model.
Inferences from Multinomial Data: Learning About a Bag of Marbles
Authors: Walley Peter
Published: December 2018

A new method is proposed for making inferences from multinomial data in cases where there is no prior information. A paradigm is the problem of predicting the colour of the next marble to be drawn from a bag whose contents are (initially) completely unknown. In such problems we may be unable to formulate a sample space because we do not know what outcomes are possible. This suggests an invariance principle: inferences based on observations should not depend on the sample space in which the observations and future events of interest are represented. Objective Bayesian methods do not satisfy this principle. This paper describes a statistical model, called the imprecise Dirichlet model, for drawing coherent inferences from multinomial data. Inferences are expressed in terms of posterior upper and lower probabilities. The probabilities are initially vacuous, reflecting prior ignorance, but they become more precise as the number of observations increases. This model does satisfy the invariance principle. Two sets of data are analysed in detail. In the first example one red marble is observed in six drawings from a bag. Inferences from the imprecise Dirichlet model are compared with objective Bayesian and frequentist inferences. The second example is an analysis of data from medical trials which compared two treatments for cardiorespiratory failure in newborn babies. There are two problems: to draw conclusions about which treatment is more effective and to decide when the randomized trials should be terminated. This example shows how the imprecise Dirichlet model can be used to analyse data in the form of a contingency table.
Estimation of Population Exposure in Ecological Studies
Authors: Plummer Martyn , Clayton David
Published: December 2018

This paper discusses design issues in 'ecological studies' —epidemiological studies in which the relationship between disease and behavioural and environmental determinants is studied at the population rather than the individual level. The number of study populations has little relevance beyond a certain point, the power and precision being limited by the total number of disease events and by the size of the sample surveys used to estimate the distributions of determinants within populations. In most circumstances, optimal design requires the size of the sample surveys in each population to be related to the number of disease events which will occur in it, and for sampling to be stratified by age and/or sex.
Discriminant Analysis by Gaussian Mixtures
Authors: Hastie Trevor , Tibshirani Robert
Published: December 2018

Fisher-Rao linear discriminant analysis (LDA) is a valuable tool for multigroup classification. LDA is equivalent to maximum likelihood classification assuming Gaussian distributions for each class. In this paper, we fit Gaussian mixtures to each class to facilitate effective classification in non-normal settings, especially when the classes are clustered. Low dimensional views are an important by-product of LDA—our new techniques inherit this feature. We can control the within-class spread of the subclass centres relative to the between-class spread. Our technique for fitting these models permits a natural blend with nonparametric versions of LDA.
Information Bias and Adjusted Profile Likelihoods
Authors: Diciccio Thomas J. , Stern Steven E. , Martin Michael A. , Young G. Alastair
Published: December 2018

The bias and information bias of the ordinary profile score statistic are both typically of order O(1). Several additive adjustments to the profile score statistic that reduce its bias to order O(n  −1) have been proposed. In certain situations, the information bias of these adjusted profile score statistics is also reduced to order O(n  −1); specifically, the modified profile likelihood of Barndorff-Nielsen yields an adjusted profile score statistic having both reduced bias and reduced information bias. In general, however, a bias reducing adjustment to the profile score statistic will not automatically reduce the order of the information bias as well. In this paper, an analytical formula is obtained for the information bias of a general bias-adjusted profile score statistic. This formula is used to compare bias reducing adjustments to the profile score statistic, as well as to construct further adjustments that reduce the information bias to O(n  −1). Several examples are presented to illustrate use of the formula for information bias. In particular, the information bias formula may be utilized in a criterion for choosing between orthogonal parameterizations for the conditional profile likelihood of Cox and Reid.
Regression Shrinkage and Selection Via the Lasso
Authors: Tibshirani Robert
Published: December 2018

We propose a new method for estimation in linear models. The ‘lasso’ minimizes the residual sum of squares subject to the sum of the absolute value of the coefficients being less than a constant. Because of the nature of this constraint it tends to produce some coefficients that are exactly 0 and hence gives interpretable models. Our simulation studies suggest that the lasso enjoys some of the favourable properties of both subset selection and ridge regression. It produces interpretable models like subset selection and exhibits the stability of ridge regression. There is also an interesting relationship with recent work in adaptive function estimation by Donoho and Johnstone. The lasso idea is quite general and can be applied in a variety of statistical models: extensions to generalized regression models and tree-based models are briefly described.
Estimation for Censored Exponential Data When the Censoring Times are Subject to Error
Authors: Phillips M. J. , Sweeting T. J.
Published: December 2018

The problem of estimating the parameter of the negative exponential distribution with censored data may be complicated by a lack of complete knowledge of the censoring times. The effect of ignoring these errors in the censoring times rather than using a complete maximum likelihood estimation approach is investigated and it is shown that the loss in efficiency is generally small for the inverted gamma model considered in this paper. The theory is supplemented by some numerical results based on an example of failure data.
Morning surge in blood pressure and blood pressure variability in Asia: Evidence and statement from the HOPE Asia Network
Authors: Sogunuru Guru P. , Kario Kazuomi , Shin Jinho , Chen Chen‐Huan , Buranakitjaroen Peera , Chia Yook C. , Divinagracia Romeo , Nailes Jennifer , Park Sungha , Siddique Saulat , Sison Jorge , Soenarta Arieska A. , Tay Jam C. , Turana Yuda , Zhang Yuqing , Hoshide Satoshi , Wang Ji‐Guang ,   HOPE Asia Network
Published: December 2018

Hypertension is a major risk factor for cardiovascular and cerebrovascular diseases. To effectively prevent end‐organ damage, maintain vascular integrity and reduce morbidity and mortality, it is essential to decrease and adequately control blood pressure (BP) throughout each 24‐hour period. Exaggerated early morning BP surge (EMBS) is one component of BP variability (BPV), and has been associated with an increased risk of stroke and cardiovascular events, independently of 24‐hour average BP. BPV includes circadian, short‐term and long‐term components, and can best be documented using out‐of‐office techniques such as ambulatory and/or home BP monitoring. There is a large body of evidence linking both BPV and EMBS with increased rates of adverse cardio‐ and cerebrovascular events, and end‐organ damage. Differences in hypertension and related cardiovascular disease rates have been reported between Western and Asian populations, including a higher rate of stroke, higher prevalence of metabolic syndrome, greater salt sensitivity and more common high morning and nocturnal BP readings in Asians. This highlights a need for BP management strategies that take into account ethnic differences. In general, long‐acting antihypertensives that control BP throughout the 24‐hour period are preferred; amlodipine and telmisartan have been shown to control EMBS more effectively than valsartan. Home and ambulatory BP monitoring should form an essential part of hypertension management, with individualized pharmacotherapy to achieve optimal 24‐hour BP control particularly the EMBS and provide the best cardio‐ and cerebrovascular protection. Future research should facilitate better understanding of BPV, allowing optimization of strategies for the detection and treatment of hypertension to reduce adverse outcomes.
Influence of processing conditions on some physical characteristics of vegetable oil expressed mechanically from Pentaclethra macrophylla Benth kernels: Response surface approach
Authors: Ogunlade Clement A. , Aremu Ademola K.
Published: December 2018

The global increase in demand for vegetable oils due to their nutritional, pharmaceutical, and industrial importance necessitates investigation on exploitation of new oil bearing crops. This study was undertaken to determine the influence of processing conditions on physical properties of oil expressed mechanically from African oil bean kernels. Central composite rotatable design of response surface methodology (RSM) at 3‐factors, 5‐levels was adopted; independent variables considered were: moisture content (MC; 8, 10, 12, 14, and 16% dry basis), heating duration (HD; 5, 10, 15, 20, and 25 min), and heating temperature (HT; 50, 70, 90, 110, 130 °C) while dependent variables (physical characteristics) include: oil impurities, density, kinematic viscosity, dynamic viscosity, specific gravity, refractive index, and color; all determined using standard methods. Optimum values were obtained using RSM. Optimum oil quality (0.044%m/m impurity, 0.92 kg/m3 density, 43.86 mm2/s kinematic viscosity, 40.8 mPa s dynamic viscosity, 0.9 specific gravity, 1.469 refractive index, and 7.7 color units) was obtained at 8% db, 11.7 min HD, and 59.3 °C HT. The quality of the expressed oil falls within permissible limits for edible oils and high nutritional importance. The processing conditions influenced the quality of the mechanically expressed African oil bean oil.

Practical applications

African oil bean is an underutilized plant with potentials for meeting increasing global demand for vegetable oil for nutritional and industrial importance. The application/usage of oil is dependent on its quality attributes which is otherwise dependent on processing parameters like moisture content, heating duration, and heating temperature. These factors need to be controlled during oil expression processes to actually the optimum conditions that will yield good quality oil. The degree of influence of the parameters on oil quality is a useful data to vegetable oil processors, food, and agricultural engineers. The quality parameters of the oil were determined and compared with international standard parameters. Mathematical models were developed to predict the yield and quality attributes of expressed oil from African oil bean kernels at various processing conditions.
Pharmacotherapy in Older Adults with Cardiovascular Disease: Report from an American College of Cardiology, American Geriatrics Society, and National Institute on Aging Workshop
Authors: Schwartz Janice B. , Schmader Kenneth E. , Hanlon Joseph T. , Abernethy Darrell R. , Gray Shelly , Dunbar‐Jacob Jacqueline , Holmes Holly M. , Murray Michael D. , Roberts Robert , Joyner Michael , Peterson Josh , Lindeman David , Tai‐Seale Ming , Downey Laura , Rich Michael W.
Published: December 2018

OBJECTIVES

To identify the top priority areas for research to optimize pharmacotherapy in older adults with cardiovascular disease (CVD).

DESIGN

Consensus meeting.

SETTING

Multidisciplinary workshop supported by the National Institute on Aging, the American College of Cardiology, and the American Geriatrics Society, February 6–7, 2017.

PARTICIPANTS

Leaders in the Cardiology and Geriatrics communities, (officers in professional societies, journal editors, clinical trialists, Division chiefs), representatives from the NIA; National Heart, Lung, and Blood Institute; Food and Drug Administration; Centers for Medicare and Medicaid Services, Alliance for Academic Internal Medicine, Patient‐Centered Outcomes Research Institute, Agency for Healthcare Research and Quality, pharmaceutical industry, and trainees and early career faculty with interests in geriatric cardiology.

MEASUREMENTS

Summary of workshop proceedings and recommendations.

RESULTS

To better align older adults’ healthcare preferences with their care, research is needed to improve skills in patient engagement and communication. Similarly, to coordinate and meet the needs of older adults with multiple comorbidities encountering multiple healthcare providers and systems, systems and disciplines must be integrated. The lack of data from efficacy trials of CVD medications relevant to the majority of older adults creates uncertainty in determining the risks and benefits of many CVD therapies; thus, developing evidence‐based guidelines for older adults with CVD is a top research priority. Polypharmacy and medication nonadherence lead to poor outcomes in older people, making research on appropriate prescribing and deprescribing to reduce polypharmacy and methods to improve adherence to beneficial therapies a priority.

CONCLUSION

The needs and circumstances of older adults with CVD differ from those that the current medical system has been designed to meet. Optimizing pharmacotherapy in older adults will require new data from traditional and pragmatic research to determine optimal CVD therapy, reduce polypharmacy, increase adherence, and meet person‐centered goals. Better integration of the multiple systems and disciplines involved in the care of older adults will be essential to implement and disseminate best practices. J Am Geriatr Soc 67:371–380, 2019.
Determination of the Minimal Important Change in the Life‐Space Assessment
Authors: Kennedy Richard E. , Almutairi Marzouq , Williams Courtney P. , Sawyer Patricia , Allman Richard M. , Brown Cynthia J.
Published: December 2018

Background/Objectives

The University of Alabama at Birmingham (UAB) Life‐Space Assessment (LSA) is a widely used measure of community mobility. To assist clinicians and researchers with assessing the significance of changes in scores, we determined the minimal important change associated with a change in health status.

Setting

Homes of community‐dwelling older adults.

Participants

A total of 419 African American and non‐Hispanic white adults 75 years and older participating in the UAB Study of Aging II, a longitudinal epidemiological study across the state of Alabama.

Intervention

None.

Measurements

Linear mixed models were used to compare change in LSA scores over 1‐month intervals (N = 9712) between participants reporting improvement, no change, or decline in activities of daily living walking scores, accounting for the correlation among scores for the same participant over time.

Results

A decline in walking status was associated with a mean decrease in LSA scores of 2.93 points (95% confidence interval [CI] = 1.69‐4.17 points), indicating lower mobility. An improvement in walking status was associated with a mean increase in LSA scores of 2.51 points (95% CI = 1.26‐3.77 points), indicating higher mobility.

Conclusion

A change in LSA scores of five or more is clinically important, exceeding the 95% CI for the change in LSA associated with change in walking status. Changes exceeding this threshold should prompt further investigation by providers with a goal of preserving mobility. J Am Geriatr Soc 67:565–569, 2019.
The Effect of Ceramic Type and Background Color on Shade Reproducibility of All‐Ceramic Restorations
Authors: Al Hamad Khaled Q. , Obaidat Ismaeel I. , Baba Nadim Z.
Published: December 2018

Purpose

To investigate the effects of background color on shade reproduction using CAD/CAM zirconia and lithium disilicate ceramics.

Materials and Methods

A plastic tooth was prepared for an all‐ceramic crown and scanned. Tooth‐shaped light background dies were manufactured. Full‐contour crowns were milled from translucent zirconia (ZT) and low translucency lithium disilicates (E [LT]). Copings from opaque zirconia (Z) and medium opacity lithium disilicate (E[MO]) ceramics were milled and layered with veneering porcelain to full contour. Metal copings were used to produce a dark background. Specimens were divided into 8 groups with 3 variables: background color, ceramic type, and translucency. Crowns were cemented using composite resin cement. Color was measured with a spectrophotometer. Color difference (∆E) was calculated using the CIEDE2000 formula between the specimens and the target shade, A1. Statistical analysis was performed using a nested design 3‐way ANOVA and Tukey multiple comparisons.

Results

The closest ∆E to target shade was produced by E (LT) (2.13 ± 0.19) on the dark background. This increased significantly to 2.90 ± 0.19 on the light background (p = 0.03). The e.max (MO) groups significantly increased (p = 0.001) to 4.40 ± 0.22 and 4.47 ± 0.4, (p = 1.00) for the dark and light backgrounds, respectively. ∆E for the zirconia groups were higher and ranged from 4.85 ± 0.48 to 5.60 ± 0.48 in the ZT groups (p = 0.04) and 6.5 ± 0.82 to 7.75 ± 0.53 (p = 0.001) for Z groups from dark to light backgrounds. There was an overall lack of chromaticity between the specimens and the target shade A1

Conclusions

Ceramic color was affected by ceramic type, background, and translucency. Lithium disilicate appeared to be better than zirconia in shade reproduction. Less‐opaque materials matched the target shade better, while opaque materials and low translucencies were more suitable for dark backgrounds.
Spatial analysis of factors influencing choice of paediatric practice for mothers from low‐income and minority populations
Authors: Goff Sarah L , Garb Jane L , Guhn‐Knight Haley , Priya Aruna , Pekow Penelope S , Lindenauer Peter K
Published: December 2018

Aim

Publicly reported quality data theoretically enable parents to choose higher‐performing paediatric practices. However, little is known about how parents decide where to seek paediatric care. We explored the relationship between geographic factors, care quality and choice of practice to see if the decision‐making process could be described in terms of a ‘gravity model’ of spatial data.

Methods

In the context of a randomised controlled trial, we used a geographic information system to calculate flow volume between practice locations and participants' homes, to locate subjects within a census tract, to determine distances between points and to perform exploratory mapping. Generalised linear modelling was then used to determine whether the data fit a gravity model, which is a spatial model that evaluates factors impacting travel from one set of locations to another.

Results

A total of 662 women and 52 paediatric practices were included in the analysis. Proximity of a practice to home was the most important factor in choosing a practice (Z = −15.01, P < 0.001). Practice size was important to a lesser extent, with larger practices more likely to be chosen (Z = 8.96, P < 0.001). A practice's performance on quality measures was associated with choice only for women who had received an intervention to increase use of quality data (Z = 2.51, P < 0.05).

Conclusions

The gravity model and the concept of flow can help explain the choice of paediatric practice in a predominantly low‐income, racially ethnic minority (non‐White) urban population. This has important ramifications for the potential impact of publicly reported quality data.
Morphogenetic theory and the constructivist institutionalist challenge
Authors: Newman Jack
Published: December 2018

This article engages with two meta‐theoretical approaches to social analysis, ‘morphogenetic theory’ and ‘constructivist institutionalism’, and specifically explores how the former fares under the critical scrutiny of the latter. The key proponent of constructivist institutionalism, Colin Hay, has offered two detailed critiques of morphogenesis that criticise its position on the foundational sociological issues of structure‐agency and material‐ideational. Although Hay's critiques are largely rejected in an overall defence of the morphogenetic approach, the process of engagement is seen to be particularly useful for morphogenetic theory because it allows a number of important clarifications to be made and it also opens up space for theoretical development. In the course of this debate, accessible introductions are given to both theories, and the similarities and differences between them are outlined, providing clarity to both. Therefore, although this article ultimately operates as a defence of morphogenetic theory, especially in the form proposed by Margaret Archer and Douglas Porpora, it finds a great deal of fruitful discussion in the constructivist institutionalist challenge.
How does “Becoming Breastfeeding Friendly” work? A Programme Impact Pathways Analysis
Authors: Buccini Gabriela , Harding Kassandra L. , Hromi‐Fiedler Amber , Pérez‐Escamilla Rafael
Published: December 2018

Becoming Breastfeeding Friendly (BBF) is an initiative designed to track country readiness and progress to effectively scale up breastfeeding programmes. BBF includes a policy toolbox that has three components: the BBF Index (BBFI), case studies, and a five‐meeting process. Mapping pathways of how BBF was implemented and utilized enables contextually grounded interpretation of its impact on breastfeeding outcomes. We conducted a programme impact pathways (PIP) analysis to identify pathways and critical quality control points (CCPs) by which BBF can enable changes in policy, legislation, and implementation of breastfeeding programmes. A BBF PIP diagram was developed, and CCPs were identified through a literature review and an iterative interviewing process with BBF investigators. The PIP was revised after feedback from BBF's Technical Advisory Group. BBF pretesting in Ghana and Mexico informed the formative evaluation of the PIP. PIP analysis identified relevant pathways between BBF activities and outcomes. Eight CCPs that could facilitate or attenuate BBF to fully impact the scaling up of the breastfeeding programmes were identified: (a) committee formed and trained; (b) committee understands BBF and BBFI; (c) committee's ability to acquire data; (d) BBFI scores; (e) criteria used for prioritizing recommendations; (f) dissemination of recommendations; (g) policymaker's reactions and media coverage; (h) committee's motivation and effective teamwork throughout BBF. Ghana and Mexico's pretesting of BBF confirmed the CCPs and provided valuable insights on potential mechanisms of BBF impacts at the country level. To further validate the PIP, a policy analysis framework is being tested in Ghana and Mexico.
Phylogeography of a widespread lizard complex reflects patterns of both geographic and ecological isolation
Authors: Gray Levi N. , Barley Anthony J. , Poe Steven , Thomson Robert C. , Nieto‐Montes de Oca Adrián , Wang Ian J.
Published: December 2018

A primary challenge for modern phylogeography is understanding how ecology and geography, both contemporary and historical, shape the spatial distribution and evolutionary histories of species. Phylogeographic patterns are the result of many factors, including geology, climate, habitat, colonization history and lineage‐specific constraints. Assessing the relative influences of these factors is difficult because few species, regions and environments are sampled in enough detail to compare competing hypotheses rigorously and because a particular phylogeographic pattern can potentially result from different evolutionary scenarios. The silky anoles (Anolis sericeus complex) of Central America and Mexico are abundant and found in all types of lowland terrestrial habitat, offering an excellent opportunity to test the relative influences of the factors affecting diversification. Here, we performed a range‐wide statistical phylogeographic analysis on restriction site‐associated DNA (RAD) markers from silky anoles and compared the phylogeographic patterns we recovered to historical and contemporary environmental and topographic data. We constructed niche models to compare niche overlap between sister lineages and conducted coalescent simulations to characterize how the major lineages of silky anoles have diverged. Our results revealed that the mode of divergence for major lineage diversification events was geographic isolation, resulting in ecological divergence between lineages, followed by secondary contact. Moreover, comparisons of parapatric sister lineages suggest that ecological niche divergence contributed to isolation by environment in this system, reflecting the natural history differences among populations in divergent environments.
OsTSD2‐mediated cell wall modification affects ion homeostasis and salt tolerance
Authors: Fang Chuanying , Li Kang , Wu Yangyang , Wang Dehong , Zhou Junjie , Liu Xiaoli , Li Yufei , Jin Cheng , Liu Xianqing , Mur Luis Alejandro José , Luo Jie
Published: December 2018

Salt stress is a major environmental threat to meeting the food demands of an increasing global population. The identification and exploitation of salt adaption mechanisms in plants are therefore vital for crop breeding. We here define the rice mutant (sstm1) whose salt sensitivity was unambiguously assigned to a single T‐DNA insertion through segregational analysis following backcrossing to the wild type line. Insertion was within OsTSD2, which encoded a pectin methyltransferase. The sstm1 and allelic mutants, collectively known as tsd2, displayed higher content of Na+ and lower level of K+ in the shoot, which is likely to lead to reduced salt tolerance. Molecular analysis revealed reduced expression of the genes maintaining K+/Na+ homeostasis in tsd2, including OsHKT1;5, OsSOS1, and OsKAT1. Furthermore, OsTSD2 influenced ion distribution between the hull and the rice seed, which could improve food safety with heavy metal pollution. Amino acid levels tended to be increased in tsd2 mutants, implicating a role of pectin in the regulation of metabolism. Taken together, we have demonstrated an important facet of salt tolerance, which implicated OsTSD2‐mediated cell wall pectin modification as a key component that could be widely applied in crop science.
Near‐IR Photochemistry for Biology: Exploiting the Optical Window of Tissue
Authors: Alabugin Alexander
Published: December 2018

Photoactive molecules enable much of modern biology and biochemistry—a vast library of fluorescent chromophores is used to track and label cellular structures and macromolecules. However, photochemistry is better known to the synthetic or physical organic chemist as a “light switch” that turns on unusual excited‐state reactivity, isomerization, or dynamic adjustment of structure. This review details a rapidly growing approach to biophotochemistry that uses low‐energy near‐IR wavelengths not only for imaging, but also for close spatial control over chemical switching events in biosystems. Emphasis is placed on topics of biomedical interest: release of gaseous biological messengers, uncaging of drugs, nano‐therapeutics, and modification of biomaterials.
Acclimation and endogenous abscisic acid in the moss Physcomitrella patens during acquisition of desiccation tolerance
Authors: Rathnayake Kumudu N. , Nelson Sven , Seeve Candace , Oliver Melvin J. , Koster Karen L.
Published: December 2018

The moss Physcomitrella patens has been used as a model organism to study the induction of desiccation tolerance (DT), but links between dehydration rate, the accumulation of endogenous abscisic acid (ABA) and DT remain unclear. In this study, we show that prolonged acclimation of P. patens at 89% relative humidity (RH) [−16 MPa] can induce tolerance of desiccation at 33% RH (−153 MPa) in both protonema and gametophore stages. During acclimation, significant endogenous ABA accumulation occurred after 1 day in gametophores and after 2 days in protonemata. Physcomitrella patens expressing the ABA‐inducible EARLY METHIONINE promoter fused to a cyan fluorescent protein (CFP) reporter gene revealed a mostly uniform distribution of the CFP increasing throughout the tissues during acclimation. DT was measured by day 6 of acclimation in gametophores, but not until 9 days of acclimation for protonemata. These results suggest that endogenous ABA accumulating when moss cells experience moderate water loss requires sufficient time to induce the changes that permit cells to survive more severe desiccation. These results provide insight for ongoing studies of how acclimation induces metabolic changes to enable DT in P. patens.
Impact of tillage and crop establishment methods on crop yields, profitability and soil physical properties in rice–wheat system of Indo‐Gangetic Plains of India
Authors: Kumar Vivak , Gathala Mahesh Kumar , Saharawat Yashpal S. , Parihar Chiter M. , Kumar Rajeev , Kumar Robin , Jat Mangi Lal , Jat Arjun S. , Mahala Deep M. , Kumar Lalit , Nayak Hari S. , Parihar Muli D. , Rai Vikas , Jewlia Hemraj , Kuri Bhola R.
Published: December 2018

Conservation agriculture (CA) based onbest‐betcrop management practices may increase crop and water productivity, as well as conserve and sustain soil health and natural resources. In a 2‐year study, we assessed the effects of tillage and crop establishment (TCE) methods on productivity, profitability and soil physical properties in a rice–wheat (RW) system. The sixTCEtreatments were used to study the impact, which are puddled transplanted rice followed by conventionally tilled wheat (CTPR–CTW), direct‐seeded rice on the flat followed by zero‐till wheat (CTDSR–ZTW), zero‐till direct‐seeded rice with residue followed by zero‐till wheat with residue (ZTDSR+R–ZTW+R), transplanted rice after rotavator puddling followed by zero‐till wheat (RTTPR–ZTW), transplanted rice after rotavator puddling followed by rotary till wheat (RTTPR–RTW) and farmer practice rice–wheat (FP–RW). Result of the study revealed that mean rice yield was not significantly affected by differentTCEmethods. Wheat planted withZTDSR+R–ZTW+R gave 30% larger grain yield thanFP‐RW. Overall, among all theTCEtreatments, theRWsystem yields and net returns were maximum underZTDSR+R–ZTW+R. The fastest mean infiltration rate (0.10 cm hr–1) was registered inZTDSR+R–ZTW+R plots, whereas the slowest was inFP‐RWplots (0.05 cm hr–1). Bulk density at 15–20 cm soil depth was least inZTDSR+R–ZTW+R (1.70 Mg m–3) and greatest inFP‐RW(1.73 Mg m–3). Results from this study revealed that conventionally tilled (CT) and transplanting of rice could be successfully replaced by adoption of the profitable doubleZT–RWsystem.
Measuring quantity and function of pneumococcal antibodies in immunoglobulin products
Authors: LaFon David C. , Nahm Moon H.
Published: December 2018

BACKGROUND

Immunoglobulin replacement therapy is a cornerstone of the treatment of primary immunodeficiencies. Preparations used for replacement therapy are processed by purifying immunoglobulins from large pools of plasma, which were obtained from healthy donors. The constituent antibodies in these products depend on the immune history of the donor pool as well as manufacturing processes that differ among manufacturers. For these reasons various methods have been proposed to examine the levels and function of antibodies to organisms such as Streptococcus pneumoniae, which frequently causes infections in patients with immunodeficiencies. Pneumococcal antibody levels or antibody function can be measured with enzyme‐linked immunosorbent assay (ELISA) or multiplexed opsonophagocytosis assay (MOPA). Although these assays were developed initially to assess the immunogenicity of pneumococcal vaccines, the techniques have been adapted to evaluate immunoglobulin products as well.

STUDY DESIGN AND METHODS

This article provides a concise review of the analytic techniques for measuring pneumococcal antibodies and prior studies of immunoglobulin products utilizing these methods.

RESULTS

Studies utilizing these assays have demonstrated that antibody levels of immunoglobulin products can vary with time, location, and manufacturer.

CONCLUSIONS

We highlight current issues and future considerations concerning measurement of pneumococcal antibodies in immunoglobulin products, and the assays used for this purpose.
Overview of antibody‐mediated immunity to S. pneumoniae: pneumococcal infections, pneumococcal immunity assessment, and recommendations for IG product evaluation
Authors: Sorensen Ricardo U. , Edgar J. David M.
Published: December 2018

Streptococcus pneumoniae (S. pneumoniae) strains colonize the nasopharynx and can cause mucosal infections in the upper airway and middle ear, pneumonias, and invasive infections like bacteremia, sepsis, and meningitis. Over 90 serotypes, defined by the structure of their capsular polysaccharides, are known. Twenty‐three of these serotypes cause most infections and several of these serotypes can develop antibiotic resistance.

Susceptibility factors that increase the susceptibility to S. pneumoniae mucosal and invasive infections include all forms of primary and secondary antibody deficiencies. Many patients affected by one of these deficiencies benefit from the regular administration of human gamma globulin (IgG) preparations.

Donors of plasma units used to prepare human IgG have varying concentrations of IgG antibodies against relevant S. pneumoniae serotypes. These antibodies are developed in response to colonization and common subclinical infections and by routine vaccination with S. pneumoniae polysaccharide vaccines. The presence of an adequate concentration of these protective antibodies against all prevalent serotypes needs to be determined to assure the effectiveness of human IgG.

All presently available methods to assess IgG antibodies against S. pneumoniae capsular polysaccharides have advantages and pitfalls that are analyzed in this review.

In vitro testing does not provide a complete or necessarily accurate measurement of the effectiveness of antibodies in vivo. For regulatory purposes, caution needs to be used in the interpretation of currently available assays that measure pneumococcal antibody levels. Monitoring S. pneumoniae infections in patients treated with IgG and tracing information about IgG lots used to treat these patients should be encouraged.
Capability and need: A framework for understanding why states create sovereign wealth funds
Authors: Eldredge Cody D.
Published: December 2018

Over the past half‐century, roughly one‐quarter of states in the international system have created sovereign wealth funds (SWFs). As a case of sovereign states investing public wealth mostly in private markets across borders, it is not altogether clear why SWFs have proliferated to this extent. What explains their spread in recent decades? In this paper, I build on a multidisciplinary literature that conceives of SWFs as a type of insurance against external risk and argue that middle economic powers that are highly exposed in global trade and capital markets are the states most likely to establish these institutions. Such states possess both the capability to create an SWF of a size sufficient to insure against risk and the need for the insurance function of a SWF by virtue of their relatively vulnerable position in the global economy. To evaluate my argument, I rely on a data set consisting of all states in the international system from 1950 to 2012 including the 48 SWFs created during that period. I find that middle economic powers with high degrees of trade and capital openness are the states most likely to create SWFs.
International survey on the impact of parasitic infections: frequency of transmission and current mitigation strategies
Authors: Leiby David A. , O'Brien Sheila F. , Wendel Silvano , Nguyen Megan L. , Delage Gilles , Devare Sushil G. , Hardiman Anthony , Nakhasi Hira L. , Sauleda Silvia , Bloch Evan M. ,   for the WPTTID Subgroup on Parasites
Published: December 2018

Background and Objectives

Globally, blood safety interventions have been successful in mitigating risk of the major transfusion‐transmitted (TT) viruses. However, strategies that address risk from parasites are comparatively limited. TT parasites are often regional in nature, posing unique challenges; we sought to understand their impact on blood safety.

Materials and Methods

An electronic questionnaire was distributed to transfusion medicine leaders in 100 countries. The survey focused on specific questions pertaining to four parasitic diseases: babesiosis, Chagas, leishmaniasis and malaria. Respondents provided data on historical TT cases, local epidemiology, policies to mitigate risk and an assessment of public health perceptions for each aetiologic agent.

Results

Twenty‐eight (28%) surveys were returned from countries in Europe (n = 13), the Americas (n = 6), Africa (n = 4), Asia (n = 3) and Oceana (n = 2). Historically, no cases of TT leishmaniasis were reported, TT babesiosis was exclusive to Canada and the USA, TT Chagas was limited to the Americas and Spain, while TT malaria was cosmopolitan. Mitigation efforts varied widely; malaria was the most frequently tested parasitic disease. The public's perception of risk for parasitic agents was low, while that of health authorities in endemic countries was higher.

Conclusion

The global impact of parasitic infections on blood safety and related mitigation efforts varied widely by parasite epidemiology, test availability, public health priorities and socioeconomic constraints. While parasites continue to pose a risk to blood safety, the successful mitigation of viral risk has elevated the prominence of TT parasites in many locations, thereby requiring consideration of mitigation efforts.