scholarly journals Dynamic Ecological Inference for Time-Varying Population Distributions Based on Sparse, Irregular, and Noisy Marginal Data

2019 ◽  
Vol 27 (3) ◽  
pp. 388-396 ◽  
Author(s):  
Devin Caughey ◽  
Mallory Wang

Social scientists are frequently interested in how populations evolve over time. Creating poststratification weights for surveys, for example, requires information on the weighting variables’ joint distribution in the target population. Typically, however, population data are sparsely available across time periods. Even when population data are observed, the content and structure of the data—which variables are observed and whether their marginal or joint distributions are known—differ across time, in ways that preclude straightforward interpolation. As a consequence, survey weights are often based only on the small subset of auxiliary variables whose joint population distribution is observed regularly over time, and thus fail to take full advantage of auxiliary information. To address this problem, we develop a dynamic Bayesian ecological inference model for estimating multivariate categorical distributions from sparse, irregular, and noisy data on their marginal (or partially joint) distributions. Our approach combines (1) a Dirichlet sampling model for the observed margins conditional on the unobserved cell proportions; (2) a set of equations encoding the logical relationships among different population quantities; and (3) a Dirichlet transition model for the period-specific proportions that pools information across time periods. We illustrate this method by estimating annual U.S. phone-ownership rates by race and region based on population data irregularly available between 1930 and 1960. This approach may be useful in a wide variety of contexts where scholars wish to make dynamic ecological inferences about interior cells from marginal data. A new R package estsubpop implements the method.

2021 ◽  
Vol 45 (5) ◽  
pp. 1340-1348
Author(s):  
Maryam Meshkinfamfard ◽  
Jon Kristian Narvestad ◽  
Johannes Wiik Larsen ◽  
Arezo Kanani ◽  
Jørgen Vennesland ◽  
...  

Abstract Background Resuscitative emergency thoracotomy is a potential life-saving procedure but is rarely performed outside of busy trauma centers. Yet the intervention cannot be deferred nor centralized for critically injured patients presenting in extremis. Low-volume experience may be mitigated by structured training. The aim of this study was to describe concurrent development of training and simulation in a trauma system and associated effect on one time-critical emergency procedure on patient outcome. Methods An observational cohort study split into 3 arbitrary time-phases of trauma system development referred to as ‘early’, ‘developing’ and ‘mature’ time-periods. Core characteristics of the system is described for each phase and concurrent outcomes for all consecutive emergency thoracotomies described with focus on patient characteristics and outcome analyzed for trends in time. Results Over the study period, a total of 36 emergency thoracotomies were performed, of which 5 survived (13.9%). The “early” phase had no survivors (0/10), with 2 of 13 (15%) and 3 of 13 (23%) surviving in the development and mature phase, respectively. A decline in ‘elderly’ (>55 years) patients who had emergency thoracotomy occurred with each time period (from 50%, 31% to 7.7%, respectively). The gender distribution and the injury severity scores on admission remained unchanged, while the rate of patients with signs on life (SOL) increased over time. Conclusion The improvement over time in survival for one time-critical emergency procedure may be attributed to structured implementation of team and procedure training. The findings may be transferred to other low-volume regions for improved trauma care.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Babak Khavari ◽  
Alexandros Korkovelos ◽  
Andreas Sahlberg ◽  
Mark Howells ◽  
Francesco Fuso Nerini

AbstractHuman settlements are usually nucleated around manmade central points or distinctive natural features, forming clusters that vary in shape and size. However, population distribution in geo-sciences is often represented in the form of pixelated rasters. Rasters indicate population density at predefined spatial resolutions, but are unable to capture the actual shape or size of settlements. Here we suggest a methodology that translates high-resolution raster population data into vector-based population clusters. We use open-source data and develop an open-access algorithm tailored for low and middle-income countries with data scarcity issues. Each cluster includes unique characteristics indicating population, electrification rate and urban-rural categorization. Results are validated against national electrification rates provided by the World Bank and data from selected Demographic and Health Surveys (DHS). We find that our modeled national electrification rates are consistent with the rates reported by the World Bank, while the modeled urban/rural classification has 88% accuracy. By delineating settlements, this dataset can complement existing raster population data in studies such as energy planning, urban planning and disease response.


Author(s):  
Silvia Melero ◽  
Alexandra Morales ◽  
Samuel Tomczyk ◽  
José Pedro Espada ◽  
Mireia Orgilés

Abstract Comorbidity between anxiety and depression symptoms is often high in children. Person-oriented statistical approaches are useful to detect heterogeneity of individuals and diverse patterns of response to treatment. This study aimed to explore the different profiles in a sample of Spanish children who received the Super Skills for Life (SSL) transdiagnostic program, to identify which profile of individuals benefited most from the intervention and the likelihood of transition of symptom patterns over time. Participants were 119 children (42.9% were female) aged 8–12 years old (M = 9.39; SD = 1.26). Children completed anxiety and depression measures at the baseline, postintervention, and 12-months follow-up. Results from latent transition analysis (LTA) revealed two groups depending on the severity of the anxiety and depression symptoms: low symptoms (LS) and high symptoms (HS). LS group remained stable and HS decreased by 25%, switching to the LS group. Children with greater social anxiety benefited most from the program over time. Furthermore, older children were more likely to improve rapidly one year after the intervention compared to younger children. This study provides information to consider when implementing preventive interventions for schoolchildren and to tailor them according to the target population characteristics to increase their effectiveness.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Alison C. Bartenslager ◽  
Nirosh D. Althuge ◽  
John Dustin Loy ◽  
Matthew M. Hille ◽  
Matthew L. Spangler ◽  
...  

Abstract Background Infectious Bovine Keratoconjunctivitis (IBK), commonly known as pinkeye, is one of the most significant diseases of beef cattle. As such, IBK costs the US beef industry at least 150 million annually. However, strategies to prevent IBK are limited, with most cases resulting in treatment with antibiotics once the disease has developed. Longitudinal studies evaluating establishment of the ocular microbiota may identify critical risk periods for IBK outbreaks or changes in the microbiota that may predispose animals to IBK. Results In an attempt to characterize the establishment and colonization patterns of the bovine ocular microbiota, we conducted a longitudinal study consisting of 227 calves and evaluated the microbiota composition over time using amplicon sequence variants (ASVs) based on 16S rRNA sequencing data and culture-based approaches. Beef calves on trial consisted of both male (intact) and females. Breeds were composed of purebred Angus and composites with varying percentages of Simmental, Angus, and Red Angus breeds. Average age at the start of the trial was 65 days ±15.02 and all calves remained nursing on their dam until weaning (day 139 of the study). The trial consisted of 139 days with four sampling time points on day 0, 21, 41, and 139. The experimental population received three different vaccination treatments (autogenous, commercial (both inactivated bacteria), and adjuvant placebo), to assess the effectiveness of different vaccines for IBK prevention. A significant change in bacterial community composition was observed across time periods sampled compared to the baseline (p < 0.001). However, no treatment effect of vaccine was detected within the ocular bacterial community. The bacterial community composition with the greatest time span between sampling time periods (98d span) was most similar to the baseline sample collected, suggesting re-establishment of the ocular microbiota to baseline levels over time after perturbation. The effect of IgA levels on the microbial community was investigated in a subset of cattle within the study. However, no significant effect of IgA was observed. Significant changes in the ocular microbiota were identified when comparing communities pre- and post-clinical signs of IBK. Additionally, dynamic changes in opportunistic pathogens Moraxella spp. were observed and confirmed using culture based methods. Conclusions Our results indicate that the bovine ocular microbiota is well represented by opportunistic pathogens such as Moraxella and Mycoplasma. Furthermore, this study characterizes the diversity of the ocular microbiota in calves and demonstrates the plasticity of the ocular microbiota to change. Additionally, we demonstrate the ocular microbiome in calves is similar between the eyes and the perturbation of one eye results in similar changes in the other eye. We also demonstrate the bovine ocular microbiota is slow to recover post perturbation and as a result provide opportunistic pathogens a chance to establish within the eye leading to IBK and other diseases. Characterizing the dynamic nature of the ocular microbiota provides novel opportunities to develop potential probiotic intervention to reduce IBK outbreaks in cattle.


2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Jiekun He ◽  
Siliang Lin ◽  
Jiatang Li ◽  
Jiehua Yu ◽  
Haisheng Jiang

AbstractThe Tibetan Plateau (TP) and surrounding regions have one of the most complex biotas on Earth. However, the evolutionary history of these regions in deep time is poorly understood. Here, we quantify the temporal changes in beta dissimilarities among zoogeographical regions during the Cenozoic using 4,966 extant terrestrial vertebrates and 1,278 extinct mammal genera. We identify ten present-day zoogeographical regions and find that they underwent a striking change over time. Specifically, the fauna on the TP was close to the Oriental realm in deep time but became more similar to the Palearctic realms more recently. The present-day zoogeographical regions generally emerged during the Miocene/Pliocene boundary (ca. 5 Ma). These results indicate that geological events such as the Indo-Asian Collision, the TP uplift, and the aridification of the Asian interior underpinned the evolutionary history of the zoogeographical regions surrounding the TP over different time periods.


1975 ◽  
Vol 142 (4) ◽  
pp. 903-913 ◽  
Author(s):  
E L Pesanti ◽  
S G Axline

Intracellular lysosomal fusion has been evaluated in cultivated mouse peritoneal macrophages by measurement of transfer of acid phosphatase to polyvinyltoluene (PVT)-containing phagolysosomes. Enzyme transfer was found to be directly and significantly related to the uptake of PVT and to be independent of time allowed for phagolysosome formation over time periods of 15 min to 18 h. In addition, the extent of transfer of lysosomal enzyme to phagolysosomes was unaffected by treatment of the cells with 10(-6) M colchicine, a dose which eradicates morphologically identifiable microtubules in this cell type within 2 h. The data indicate that intracellular fusion of lysosomes with phagosomes in the macrophage does not require formed microtubules and suggest that fusion occurs promptly after interiorization of inert particles.


2007 ◽  
Vol 32 (3) ◽  
pp. 319-340 ◽  
Author(s):  
Nancy Ettlinger

Departing from tendencies to bound precarity in particular time periods and world regions, this article develops an expansive view of precarity over time and across space. Beyond effects of specific global events and macroscale structures, precarity inhabits the microspaces of everyday life. However, people attempt to disengage the stress of precarious life by constructing the illusion of certainty. Reflexive denial of precarious life entails essentialist strategies that implicitly or explicitly classify and homogenize people and phenomena, legitimize the constructed boundaries, and in the process aim at eliminating difference and possibilities for negotiation; the tension between these goals and material realities helps explain misrepresentations that can be catastrophic at multiple scales, re-creating precarity. Reactions to 9/11 by the Bush administration represent a case in point of reflexive denial of precarity through strategies that created illusions of certainty with deleterious results. Normatively, the paradox of precarious life and reflexive denials prompts questions as to how urges for certainty in the context of precarity might be constructively channeled. the author approaches this challenge in the final section by drawing from a nexus of concerns about post-Habermasian radical democracy, individual thought and feeling, and network dynamics. Whereas Hardt and Negri reverse the direction of the Foucauldian concept of biopower from top-down to bottom-up, the author draws from Foucault's concept of governmentality in relation to resistance to imagine a cooperative politics operating within as well as across scales.


2018 ◽  
Vol 4 ◽  
pp. 237802311881180 ◽  
Author(s):  
Jonathan J. B. Mijs

In this figure I describe the long trend in popular belief in meritocracy across the Western world between 1930 and 2010. Studying trends in attitudes is limited by the paucity of survey data that can be compared across countries and over time. Here, I show how to complement survey waves with cohort-level data. Repeated surveys draw on a representative sample of the population to describe the typical beliefs held by citizens in a given country and period. Leveraging the fact that citizens surveyed in a given year were born in different time-periods allows for a comparison of beliefs across birth cohorts. The latter overlaps with the former, but considerably extends the time period covered by the data. Taken together, the two measures give a “triangulated” longitudinal record of popular belief in meritocracy. I find that in most countries, popular belief in meritocracy is (much) stronger for more recent periods and cohorts.


2018 ◽  
Vol 41 (2) ◽  
pp. 260-279 ◽  
Author(s):  
Christian Burgers ◽  
Kathleen Ahrens

AbstractThe literature provides diverging perspectives on the universality and stability of economic metaphors over time. This article contains a diachronic analysis of economic metaphors describing trade in a corpus of 225 years of US State of the Union addresses (1790–2014). We focused on two types of change: (i) replacement of a source domain by another domain and (ii) change in mapping within a source domain. In our corpus, five source domains of trade were predominant: (i) PhysicalObject, (ii) Building, (iii) Container, (iv) Journey, and (v) LivingBeing. Only the relative frequency of the Container source domain was related to time. Additionally, mappings between source and target domains were mostly stable. Nevertheless, our analyses suggest that the Trade metaphors in our corpus are related to concreteness in a more nuanced way as typically assumed in conceptual metaphor theory: metaphors high in the concreteness dimension of physicality and low in the concreteness dimension of specificity are likeliest to be used over longer time periods, by providing communicators with freedom to adjust the metaphor to changing societal circumstances.


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