bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluating the use of bootstrapping in cohort studies conducted with 1:1 propensity score matching—A plasmode simulation study
Authors: Desai Rishi J. , Wyss Richard , Abdia Younathan , Toh Sengwee , Johnson Margaret , Lee Hana , Karami Sara , Major Jacqueline M. , Nguyen Michael , Wang Shirley V. , Franklin Jessica M. , Gagne Joshua J. 
Published: April 2019

AbstractPurposeBootstrapping can account for uncertainty in propensity score (PS) estimation and matching processes in 1:1 PS‐matched cohort studies. While theory suggests that the classical bootstrap can fail to produce proper coverage, practical impact of this theoretical limitation in settings typical to pharmacoepidemiology is not well studied.MethodsIn a plasmode‐based simulation study, we compared performance of the standard parametric approach, which ignores uncertainty in PS estimation and matching, with two bootstrapping methods. The first method only accounted for uncertainty introduced during the matching process (the observation resampling approach). The second method accounted for uncertainty introduced during both PS estimation and matching processes (the PS reestimation approach). Variance was estimated based on percentile and empirical standard errors, and treatment effect estimation was based on median and mean of the estimated treatment effects across 1000 bootstrap resamples. Two treatment prevalence scenarios (5% and 29%) across two treatment effect scenarios (hazard ratio of 1.0 and 2.0) were evaluated in 500 simulated cohorts of 10 000 patients each.ResultsWe observed that 95% confidence intervals from the bootstrapping approaches but not the standard approach, resulted in inaccurate coverage rates (98%‐100% for the observation resampling approach, 99%‐100% for the PS reestimation approach, and 95%‐96% for standard approach). Treatment effect estimation based on bootstrapping approaches resulted in lower bias than the standard approach (less than 1.4% vs 4.1%) at 5% treatment prevalence; however, the performance was equivalent at 29% treatment prevalence.ConclusionUse of bootstrapping led to variance overestimation and inconsistent coverage, while coverage remained more consistent with parametric estimation.
Exposure to a Motor Vehicle Collision and the Risk of Future Neck Pain: A Systematic Review and Meta‐Analysis
Authors: Nolet Paul S. , Emary Peter C. , Kristman Vicki L. , Murnaghan Kent , Zeegers Maurice P. , Freeman Michael D. 
Published: April 2019

ObjectiveTo summarize the literature that has examined the association between a motor vehicle collision (MVC) related neck injury and future neck pain (NP) in comparison with the population that has not been exposed to neck injury from an MVC.Literature SurveyNeck injury resulting from an MVC is associated with a high rate of chronicity. Prognosis studies indicate 50% of injured people continue to experience NP a year after the collision. This is difficult to interpret due to the high prevalence of NP in the general population.MethodologyWe performed a systematic review of the literature using five electronic databases, searching for risk studies on exposure to an MVC and future NP published from 1998 to 2018. The outcome of interest was future NP. Eligible risk studies were critically appraised using the modified Quality in Prognosis Studies (QUIPS) instrument. The results were summarized using best‐evidence synthesis principles, a random effects meta‐analysis, metaregression, and testing for publication bias was performed with the pooled data.SynthesisEight articles were identified of which seven were of lower risk of bias. Six studies reported a positive association between a neck injury in an MVC and future NP compared to those without a neck injury in an MVC. Pooled analysis of the six studies indicated an unadjusted relative risk of future NP in the MVC exposed population with neck injury of 2.3 (95% CI [1.8, 3.1]), which equates to a 57% attributable risk under the exposed. In two studies where exposed participants were either not injured or injury status was unknown, there was no increased risk of future NP.ConclusionsThere was a consistent positive association among studies that have examined the association between MVC‐related neck injury and future NP. These findings are of potential interest to clinicians, insurers, patients, governmental agencies, and the courts.Level of EvidenceI.
A surface temperature and moisture intercomparison study of the Weather Research and Forecasting model, in‐situ measurements and satellite observations over the Atacama Desert
Authors: Fonseca Ricardo , Zorzano‐Mier María‐Paz , Azua‐Bustos Armando , González‐Silva Carlos , Martín‐Torres Javier 
Published: April 2019

AbstractGood knowledge of the environmental conditions of deserts on Earth is relevant for climate studies. The Atacama Desert is of particular interest as it is considered to be the driest region on Earth. We have performed simulations using the Weather Research and Forecasting (WRF) model over the Atacama Desert for two week‐long periods in the austral winter season coincident with surface temperature and relative humidity in‐situ observations at three sites. We found that the WRF model generally overestimates the daytime surface temperature, with biases of up to 11°C, despite giving a good simulation of the relative humidity. In order to improve the agreement with observed measurements, we conducted sensitivity experiments in which the surface albedo, soil moisture content and five tuneable parameters in the Noah Land Surface Model (namely soil porosity, soil suction, saturated soil hydraulic conductivity, the b parameter used in hydraulic functions and the quartz fraction) are perturbed. We concluded that an accurate simulation is not possible, most likely because the Noah Land Surface Model does not have a groundwater table that may be shallow in desert regions. The WRF‐predicted land surface temperature is also evaluated against that estimated from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument. While at night the satellite‐derived and ground‐based measurements are generally in agreement, during the day MODIS estimates are typically lower by as much as 17°C. This is attributed to the large uncertainty in the MODIS‐estimated land surface temperatures in arid and semi‐arid regions. The findings of this work highlight the need for ground‐based observational networks in remote regions such as the Atacama Desert where satellite‐derived and model products may not be very accurate.
A continuous‐time Markov chain model for redundancy allocation problem: An economic analysis
Authors: Tohidi Hossein , Chavoshi Saeed , Bahmaninezhad Azadeh 
Published: April 2019

AbstractReliability of an engineering system can be improved by investing on redundant (spare) parts. However, the cost‐efficiency of such an investment is a significant concern that needs to be taken into consideration in practice. To do so, a continuous‐time Markov chain (CTMC) model is presented in this paper to analyze the system's reliability by allocating redundant components. The developed model can also capture the system's repair and failure conditions by defining appropriate states in CTMC. Subsequently, the net present value (NPV) approach is utilized for a variety of scenarios to investigate the effectiveness of investment on spare parts using the break‐even point (BEP) analysis. Afterwards, a comprehensive analysis is carried out to examine the impact of input parameters including interest rate, initial cost of investment, and periodic profit on the decision making process to find the optimal number of spare parts.
Concise Review: Precision Matchmaking: Induced Pluripotent Stem Cells Meet Cardio-Oncology
Authors: Nair Pooja , Prado Maricela , Perea-Gil Isaac , Karakikes Ioannis 
Published: April 2019

Abstract
As common chemotherapeutic agents are associated with an increased risk of acute and chronic cardiovascular complications, a new clinical discipline, cardio-oncology, has recently emerged. At the same time, the development of preclinical human stem cell-derived cardiovascular models holds promise as a more faithful platform to predict the cardiovascular toxicity of common cancer therapies and advance our understanding of the underlying mechanisms contributing to the cardiotoxicity. In this article, we review the recent advances in preclinical cancer-related cardiotoxicity testing, focusing on new technologies, such as human induced pluripotent stem cell-derived cardiomyocytes and tissue engineering. We further discuss some of the limitations of these technologies and present future directions. Stem Cells Translational Medicine 2019;8:758–767
Synergetic Coupling of Lithiophilic Sites and Conductive Scaffolds for Dendrite‐Free Lithium Metal Anodes
Authors: Chen Xiao‐Ru , Li Bo‐Quan , Zhao Chang‐Xin , Zhang Rui , Zhang Qiang 
Published: April 2019

AbstractLithium metal is highly considered as an ideal anode material because of its ultrahigh theoretical capacity of 3680 mA h g−1 and the lowest potential of −3.04 V versus the standard hydrogen electrode. However, uncontrollable lithium dendrite growth severely impedes the practical applications of lithium metal batteries. The introduction of a lithium host is an effective strategy to inhibit lithium dendrite growth, where lithiophilicity and conductivity of the lithium host play the dominant role. In this contribution, the synergistic effect of lithiophilic sites and conductive scaffolds is investigated to construct an optimized lithium host for dendrite‐free lithium metal anodes. Consequently, the lithium host with balanced lithiophilicity and conductivity demonstrates excellent electrochemical performances regarding to high Coulombic efficiency of 98% stable for 300 cycles at 1.0 mA cm−2 and improved capacity retention of 86.2% after 100 cycles in LiFePO4 full cells. The synergistic coupling of lithiophilicity and conductivity of lithium hosts enhances the understanding of lithiophilic chemistry to achieve next‐generation high‐performance batteries.
The social, the ecological, and the adaptive. Von Bertalanffy's general systems theory and the adaptive governance of social‐ecological systems
Authors: Van Assche Kristof , Verschraegen Gert , Valentinov Vladislav , Gruezmacher Monica 
Published: April 2019

AbstractBased on biological insights, Ludwig von Bertalanffy coined general systems theory (GST) and later expanded his perspective, exploring what GST could mean for other disciplines and other types of systems. We make a case for the relevance, or rather, the importance, of GST for coming to a new understanding of the resilience of social‐ecological systems and the possible forms of adaptive governance that might increase such resilience. After analyzing the conceptual structure of the resilience paradigm and of GST, we identify concepts in resilience thinking where GST provides new confirmation or modifies the perspective: complexity, evolution, self‐organization, and adaptation. We discuss post‐Bertalanffy developments in the interdisciplinary and twinned fields of systems theory and complexity studies that can provide bridging concepts between GST and resilience thinking. In conclusion, we emphasize the need for both cognitive and institutional resilience to foster adaptive governance. We highlight the management of couplings between systems and the switching between forms of understanding and forms of organization, where self‐organization and more centralized forms of steering can alternate and combine.
Concise Review: Genetic and Epigenetic Regulation of Cardiac Differentiation from Human Pluripotent Stem Cells
Authors: Fujita Jun , Tohyama Shugo , Kishino Yoshikazu , Okada Marina , Morita Yuika 
Published: April 2019

Abstract
Human pluripotent stem cells (hPSCs), including both embryonic stem cells and induced pluripotent stem cells, are the ideal cell sources for disease modeling, drug discovery, and regenerative medicine. In particular, regenerative therapy with hPSC-derived cardiomyocytes (CMs) is an unmet medical need for the treatment of severe heart failure. Cardiac differentiation protocols from hPSCs are made on the basis of cardiac development in vivo. However, current protocols have yet to yield 100% pure CMs, and their maturity is low. Cardiac development is regulated by the cardiac gene network, including transcription factors (TFs). According to our current understanding of cardiac development, cardiac TFs are sequentially expressed during cardiac commitment in hPSCs. Expression levels of each gene are strictly regulated by epigenetic modifications. DNA methylation, histone modification, and noncoding RNAs significantly influence cardiac differentiation. These complex circuits of genetic and epigenetic factors dynamically affect protein expression and metabolic changes in cardiac differentiation and maturation. Here, we review cardiac differentiation protocols and their molecular machinery, closing with a discussion of the future challenges for producing hPSC-derived CMs. Stem Cells 2019;37:992–1002
Quantitative analysis of the yeast pheromone pathway
Authors: Shellhammer James P. , Pomeroy Amy E. , Li Yang , Dujmusic Lorena , Elston Timothy C. , Hao Nan , Dohlman Henrik G. 
Published: April 2019

AbstractThe pheromone response pathway of the yeastSaccharomyces cerevisiaeis a well‐established model for the study of G proteins and mitogen‐activated protein kinase (MAPK) cascades. Our longstanding ability to combine sophisticated genetic approaches with established functional assays has provided a thorough understanding of signalling mechanisms and regulation. In this report, we compare new and established methods used to quantify pheromone‐dependent MAPK phosphorylation, transcriptional induction, mating morphogenesis, and gradient tracking. These include both single‐cell and population‐based assays of activity. We describe several technical advances, provide example data for benchmark mutants, highlight important differences between newer and established methodologies, and compare the advantages and disadvantages of each as applied to the yeast model. Quantitative measurements of pathway activity have been used to develop mathematical models and reveal new regulatory mechanisms in yeast. It is our expectation that experimental and computational approaches developed in yeast may eventually be adapted to human systems biology and pharmacology.
Populist leaders and political parties
Authors: Barber N. W. 
Published: April 2019

AbstractPopulism is a particular type of constitutional pathology; a brand of groupthink in which a leader establishes a direct connection with the people and, by virtue of this connection, is able to govern outside the established constitutional processes of the state. This Article reflects on the interaction between populism and political parties. It argues that one of the roles of political parties is to act as a medium between political elites and the people; a medium that can, or should, enable the people to exercise control over this elite through their membership of parties. Populism therefore presents a threat to the proper operation of political parties, and the proper operation of political parties correspondingly threatens populism.This Article begins by reflecting on the nature of populism. It does not pretend to provide a complete account of that phenomenon, but rather aspires to identify one strand of populist rule: A particular type of connection between the leader and her people. Second, the paper reflects on the constitutional role of political parties. Whilst political parties have often been treated critically in British constitutional scholarship, it will be argued that they are essential to the success of the democratic process: Modern representative democracy cannot function in their absence. Finally, these two sections of the paper will be drawn together: One explanation for the rise of populism is the weakness of political parties, and one way of combating, or mitigating, populism is for the state, and the citizenry, to support and facilitate parties. This Article suggests a correlation between the decline of political parties and the rise of populism, but it cautiously avoids making claims of causation. It could be that the decline of political parties leads to the rise of populism, as voters who are faced with a choice of superannuated parties turn, instead, to charismatic individuals. Or it could be that the rise of populism leads to the decline of political parties, as voters develop a direct relationship with leaders and, as a result, cease to engage with each other within the context of parties. Or, perhaps, these interactions might occur together, forming a feedback loop, with the decline of parties leading to the rise of populism which, in turn, hastens party decay.
Impact of misinformation in temporal network epidemiology
Authors: Holme Petter , Rocha Luis E. C. 
Published: April 2019

AbstractWe investigate the impact of misinformation about the contact structure on the ability to predict disease outbreaks. We base our study on 31 empirical temporal networks and tune the frequencies in errors in the node identities or time stamps of contacts. We find that for both these spreading scenarios, the maximal misprediction of both the outbreak size and time to extinction follows an stretched exponential convergence as a function of the error frequency. We furthermore determine the temporal-network structural factors influencing the parameters of this convergence.
Beyond homophily: Incorporating actor variables in statistical network models
Authors: Snijders Tom A.B. , Lomi Alessandro 
Published: April 2019

AbstractWe consider the specification of effects of numerical actor attributes, having an interval level of measurement, in statistical models for directed social networks. A fundamental mechanism is homophily or assortativity, where actors have a higher likelihood to be tied with others having similar values of the variable under study. But there are other mechanisms that may also play a role in how the attribute values of two actors influence the likelihood of a tie between them. We discuss three additional mechanisms: aspiration, the tendency to send more ties to others having high values; attachment conformity, sending more ties to others whose values are close to the “social norm”; and sociability, where those having higher values will tend to send more ties generally. These mechanisms may operate jointly, and then their effects will be confounded. We present a specification representing these effects simultaneously by a four-parameter quadratic function of the values of sender and receiver. Flexibility can be increased by a five-parameter extension. We argue that for numerical actor attributes having important effects on directed networks, these specifications may provide an improvement. An illustration is given of dependence of advice ties on academic grades, analyzed by the Stochastic Actor-oriented Model.
Reparative Justice for Climate Refugees
Authors: Buxton Rebecca 
Published: April 2019

AbstractThis paper sketches an account of reparative justice for climate refugees, focusing on total land loss due to sea-level rise. I begin by outlining the harm of this loss in terms of self-determination and cultural heritage. I then consider, first, who is owed these reparations? Second, who should pay such reparations? Third, in what form should the reparations be paid? I end with thoughts on the project of reparative justice more generally, arguing that such obligations do not depend upon a perfect account of how reparations might be fulfilled; we simply have an obligation to shoot the arrow as close to the target as we can.
The three waves of Arctic urbanisation. Drivers, evolutions, prospects
Authors: Laruelle Marlene 
Published: April 2019

AbstractThe 2014 Arctic Human Development Report identified “Arctic settlements, cities, and communities” as one of the main gaps in knowledge of the region. This article looks at circumpolar urbanisation trends. It dissociates three historical waves of Arctic urbanisation: from the sixteenth century to the early twentieth century (the “colonial” wave), from the 1920s to the 1980s in the specific case of the Soviet urbanisation of the Arctic (the “Soviet” wave), and from the 1960s−70s to the present as a circumpolar trend (the “globalized” wave). It then discusses the three drivers of the latest urbanisation wave (resources, militarisation, and public services) and the prospects for Arctic cities’ sustainability in the near future.
Informal care provision across multiple generations in China
Authors: Falkingham Jane , Evandrou Maria , Qin Min , Vlachantoni Athina 
Published: April 2019

AbstractWith increasing life expectancy, changes in family structure and, most recently, the relaxation of the hitherto strict family planning policies, understanding how mid-life individuals support multiple generations, particularly their older parents and younger grandchildren, is of increasing research and policy significance in China. This paper analyses data from the 2011 China Health and Retirement Longitudinal Study (CHARLS) to examine the characteristics of Chinese mid-life individuals aged 45–64 who are potentially being ‘sandwiched’ between providing care to older parents/parents-in-law and/or younger grandchildren (under age 16). Binary logistic and multinomial regression models shed light on the factors associated with providing support to one generation or multiple generations. The results highlight that amongst the Chinese mid-life sandwich generation, 58 per cent only provide care to their young grandchildren, 23 per cent only provide care to their parents/parents-in-law, whilst 15 per cent are simultaneously supporting both generations. Rather than acting as competing demands upon the mid-lifers’ time, the multivariate analysis provides evidence that the provision of intergenerational care is complementary, with caring for grandchildren increasing the probability of also supporting one's parents/parents-in-law, andvice versa. However, an increase in the number of younger grandchildren has a negative impact on the care provided to older parents/parents-in-law, indicating that at higher care intensities there may be competing demands across the generations.
Chinese preschoolers’ acquisition of temporal adverbs indicating past, present, and future: a corpus-based study
Authors: LIANG Lu Yao , WU Dandan , LI Hui 
Published: April 2019

AbstractThis study investigated the development of temporal adverbs in early childhood Mandarin. All cases of temporal adverbs indicating the past, present, and future were extracted from the Early Child Mandarin Corpus (168 children in four age groups: 2;6, 3;6, 4;6, 5;6). Data analyses indicated: (1) Mandarin-speaking children produced a repertoire of 21 types of temporal adverbs, and the children in the first age group (M = 2;6) were capable of using temporal adverbs to denote past, present, and future events; (2) within each age group, the children produced significantly more future temporal adverbs than the other two subtypes; and (3) there was a significant age effect that, with increased age, more children were able to produce all subtypes of temporal adverbs. Overall, findings of this corpus-based investigation shed light upon Chinese children's early-attained ability to express the three fundamental notions of time by resorting to the appropriate linguistic devices.