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Author(s):  
Ali Enayat

AbstractA model $${\mathcal {M}}$$ M of ZF is said to be condensable if $$ {\mathcal {M}}\cong {\mathcal {M}}(\alpha )\prec _{\mathbb {L}_{{\mathcal {M}}}} {\mathcal {M}}$$ M ≅ M ( α ) ≺ L M M for some “ordinal” $$\alpha \in \mathrm {Ord}^{{\mathcal {M}}}$$ α ∈ Ord M , where $$\mathcal {M}(\alpha ):=(\mathrm {V}(\alpha ),\in )^{{\mathcal {M}}}$$ M ( α ) : = ( V ( α ) , ∈ ) M and $$\mathbb {L}_{{\mathcal {M}}}$$ L M is the set of formulae of the infinitary logic $$\mathbb {L}_{\infty ,\omega }$$ L ∞ , ω that appear in the well-founded part of $${\mathcal {M}}$$ M . The work of Barwise and Schlipf in the 1970s revealed the fact that every countable recursively saturated model of ZF is cofinally condensable (i.e., $${\mathcal {M}}\cong {\mathcal {M}}(\alpha ) \prec _{\mathbb {L}_{{\mathcal {M}}}}{\mathcal {M}}$$ M ≅ M ( α ) ≺ L M M for an unbounded collection of $$\alpha \in \mathrm {Ord}^{{\mathcal {M}}}$$ α ∈ Ord M ). Moreover, it can be readily shown that any $$\omega $$ ω -nonstandard condensable model of $$\mathrm {ZF}$$ ZF is recursively saturated. These considerations provide the context for the following result that answers a question posed to the author by Paul Kindvall Gorbow.Theorem A.Assuming a modest set-theoretic hypothesis, there is a countable model $${\mathcal {M}}$$ M of ZFC that is bothdefinably well-founded (i.e., every first order definable element of $${\mathcal {M}}$$ M is in the well-founded part of $$\mathcal {M)}$$ M ) andcofinally condensable. We also provide various equivalents of the notion of condensability, including the result below.Theorem B.The following are equivalent for a countable model$${\mathcal {M}}$$ M of $$\mathrm {ZF}$$ ZF : (a) $${\mathcal {M}}$$ M is condensable. (b) $${\mathcal {M}}$$ M is cofinally condensable. (c) $${\mathcal {M}}$$ M is nonstandard and $$\mathcal {M}(\alpha )\prec _{\mathbb {L}_{{\mathcal {M}}}}{\mathcal {M}}$$ M ( α ) ≺ L M M for an unbounded collection of $$ \alpha \in \mathrm {Ord}^{{\mathcal {M}}}$$ α ∈ Ord M .


2021 ◽  
Vol 12 ◽  
Author(s):  
Megan Stubbs-Richardson ◽  
H. Colleen Sinclair ◽  
Ben Porter ◽  
Jessica Weiss Utley

Research has sought to identify the conditions under which rejection leads to retaliation. The Multimotive Model (MMM) proposes that there are three primary behavioral responses to rejection: prosocial (e.g., befriending others), asocial (e.g., withdrawal), and antisocial behavior (e.g., aggression toward others). In this study, we conducted the first full test of the MMM as well as expanded the model. Based on research linking aggression and “perceived groupness,” construal items were added assessing whether the rejection was perceived as extending beyond the individual to one's peers. We also included self-harm behavioral responses as this outcome was not sufficiently captured by existing antisocial or asocial operationalizations. This expanded model was then tested with two high school student samples (Ns of 231 and 374) who reported experiencing aggressive rejection (i.e., experienced physical, verbal, relational, or cyber aggression from peers). The MMM was compared to a saturated model separately in each of the two datasets using structural equation modeling. Results indicate that the saturated model provides a better fit for the data than the MMM across all models examined (all p < 0.001). In part, this is due to certain paths having different associations than hypothesized. For example, perceiving the rejection as carrying a higher cost was predicted to promote prosocial behavior, where instead it predicted asocial responses. Perceived groupness was the strongest predictor of antisocial responses. Self-harm outcomes were significantly and consistently associated with higher perceived costs across the models. These results and others will be discussed in the context of how we can better encourage prosocial and discourage antisocial and self-harm responses to social rejection, including bullying.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Natan Feter ◽  
Jayne S. Leite ◽  
Daniel Umpierre ◽  
Eduardo L. Caputo ◽  
Airton J. Rombaldi

Abstract Background We aimed to test which life course model best described the association between leisure-time physical activity (LTPA) and multimorbidity at age 55. We analyzed data from birth to age 55 using the database from the 1958 National Child Development Survey. Methods Multimorbidity was considered as the presence of more than one chronic condition. LTPA was measured through questionnaires from 1965 (age 7) to 2013 (age 55), which were applied in eight different occasions. We compared the fit of a series of nested adjusted logistic regression models (representing either the critical, accumulation or sensitive period models) with a fully saturated model. Data were reported as odds ratio (OR) and 95% confidence interval (CI). Results From an eligible sample of 15,613 cohort members, 9137 were interviewed in the latest sweep (58.5%). Men were more physically active than women at ages 11, 16, and 23 (p < 0.001). LTPA every day in the week was more frequent in women than men in ages 33, 42, and 50 (p < 0.001). The prevalence of multimorbidity at age 55 was 33.0% (n = 2778). The sensitive analysis revealed that LTPA during adolescence (OR: 0.83; 95% CI: 0.70, 0.98) and mid adult life (age 50 and 55; OR: 0.82; 95%CI: 0.69, 0.98) have a stronger effect on the risk for multimorbidity at age 55 considering all other life stages in the model. Also, adolescence showed a critical independent effect on the risk for multimorbidity (OR: 0.82; 95%CI: 0.70, 0.97). No difference was found between those models. Conclusions These data support the notion of a protective physical activity “legacy” at early ages of childhood against multimorbidity at older ages. We highlight the need for LTPA promotion through intervention tailored especially on schooling and older ages in order to reduce the burden of multimorbidity.


2021 ◽  
Vol 9 (2) ◽  
pp. 381
Author(s):  
Robert Starke ◽  
Maysa Lima Parente Fernandes ◽  
Daniel Kumazawa Morais ◽  
Iñaki Odriozola ◽  
Petr Baldrian ◽  
...  

Revealing the relationship between taxonomy and function in microbiomes is critical to discover their contribution to ecosystem functioning. However, while the relationship between taxonomic and functional diversity in bacteria and fungi is known, this is not the case for archaea. Here, we used a meta-analysis of 417 completely annotated extant and taxonomically unique archaeal genomes to predict the extent of microbiome functionality on Earth contained within archaeal genomes using accumulation curves of all known level 3 functions of KEGG Orthology. We found that intergenome redundancy as functions present in multiple genomes was inversely related to intragenome redundancy as multiple copies of a gene in one genome, implying the tradeoff between additional copies of functionally important genes or a higher number of different genes. A logarithmic model described the relationship between functional diversity and species richness better than both the unsaturated and the saturated model, which suggests a limited total number of archaeal functions in contrast to the sheer unlimited potential of bacteria and fungi. Using the global archaeal species richness estimate of 13,159, the logarithmic model predicted 4164.1 ± 2.9 KEGG level 3 functions. The non-parametric bootstrap estimate yielded a lower bound of 2994 ± 57 KEGG level 3 functions. Our approach not only highlighted similarities in functional redundancy but also the difference in functional potential of archaea compared to other domains of life.


2021 ◽  
Author(s):  
Jihong Zhang ◽  
Jonathan Templin ◽  
Catherine E. Mintz

Posterior Predictive Model Checking (PPMC) is frequently used for model fit evaluation in Bayesian Confirmatory Factor Analysis (BCFA). In standard PPMC procedures, model misfit is quantified by the location of a ML-based estimate to the predictive distribution of a statistic for a model. When the ML-based point estimate is far away from the center of the density of the posterior predictive distribution, model fit is poor. One main critique of such standard PPMC procedures is the strong link to the ML-based point estimates of the observed data. Not included in this approach, however, is how variable the ML-based point estimates are and their use in general as the reference point for Bayesian analyses. We propose a new method of PPMC based on the Posterior Predictive distribution of Bayesian saturated model for BCFA models. The method uses the predictive distribution from parameters of the posterior distribution of the saturated model as reference to detect the local misfit of hypothesized models. The results of the simulation study suggest that the saturated model PPMC approach was an accurate method of determining local model misfit and could be used for model comparison. A real example is also provided in this study.


Author(s):  
Cezary Cieśliński

AbstractWe present a construction of a truth class (an interpretation of a compositional truth predicate) in an arbitrary countable recursively saturated model of first-order arithmetic. The construction is fully classical in that it employs nothing more than the classical techniques of formal proof theory.


2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Priscilla Muscat ◽  
John Weinman ◽  
Emanuel Farrugia ◽  
Liberato Camilleri ◽  
Joseph Chilcot

Abstract Background Illness perceptions have been shown to predict a range of psychosocial and clinical outcomes in kidney disease; including quality of life, distress, treatment adherence and even survival in end-stage renal disease patients on dialysis. The aim of this study was to evaluate whether illness perceptions impact mortality in incident predialysis Chronic Kidney Disease (CKD) patients. Methods Over the study period between September 2015 and June 2019, a total of 200 participants with predialysis CKD were recruited from the Nephrology Outpatient’s clinics at Mater Dei Hospital, Malta. The participants were followed up until June 2019, and the mortality information was collected. Cox proportional hazards models were used to examine the association between illness perceptions, and mortality risk, after adjustment for covariates including distress, kidney function, co-morbidity and psychological distress. Results Of the 200 cases available for analysis, there were 43 deaths. The mean survival time was 718.55 days (min. 3 days, max. 1297 days). The cumulative survival 1-year post the assessment of the Revised Illness Perceptions Questionnaire (IPQ–R) was 93%. Stronger identity beliefs (HR = 1.199, 95% CI: 1.060–1.357, p = 0.004), perceptions of a chronic timeline (HR = 1.065, 95% CI: 1.003–1.132, p = 0.041), personal control beliefs (HR = 0.845, 95% CI: 0.748–0.955, p = 0.007) and perceptions of control over the treatment (HR = 0.812, 95% CI: 0.725–0.909, p = 0.000) demonstrated a significant association with mortality after controlling covariates. In a subsequent saturated model, perceived identity, chronic timeline and treatment control perceptions remained significant predictors of mortality, together with serum albumin, comorbidities and urea. Conclusions CKD patients’ perceptions of treatment control, perceptions of a chronic timeline and perceived illness identity predict survival independently of clinical prognostic factors, including kidney function and co-morbidity. Illness perceptions are important and potentially modifiable risk factors in CKD. Further studies are required to test whether the assessment and the implementation of psychological interventions aimed to modify maladaptive illness perceptions influence clinical outcomes in CKD.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Jamal S Rana ◽  
Jennifer Y Liu ◽  
Howard H Moffet ◽  
Andrew Karter

Introduction: Studies evaluating the relationship of severe hypoglycemia (SH) with the risk of atherosclerotic cardiovascular disease (ASCVD) events are limited by size, confounding and inconsistent outcome definitions. The aim of this study was to assess the association of SH, as defined by hypoglycemia-related hospital utilization, with risk of ASCVD. Methods: We conducted an observational cohort study of adults with diabetes with or without established ASCVD (as of 1/1/2014). All subjects were members of Kaiser Permanente Northern California, an integrated health care delivery system. Baseline was determined by the date of the first hypoglycemia-related utilization (primary diagnosis of hypoglycemia in the emergency department or principal diagnosis in the hospital) during 1/1/2013 - 12/31/2013. Baseline for those without SH, was a randomly assigned date in 2013. Multivariate Cox proportional hazard models were specified to estimate hazard ratios (HRs) for SH in adjusted models of time to incident ASCVD events. This outcome was defined as a composite of nonfatal myocardial infarction, ischemic stroke, or coronary heart disease death through 12/31/2017. Results: Among 233,696 eligible individuals, mean age was 63.6 years, 47.6% were women, and mean follow-up was 3.8 years. There were 2,179 episodes of SH. Age-sex-race adjusted risk of ASCVD among those with SH versus those without was HR 2.59 (95% CI 2.3-2.9). When additionally adjusted for prior ASCVD, the HR was still more than double, HR 2.32 (95% CI 2.1-2.6). In a fully saturated model with additional adjustments for diabetes type, diabetes duration, HbA1c, GFR, Charlson score, insulin use, sulfonylureas, and quartiles of neighborhood deprivation, SH was associated with a 30% increased risk (HR 1.31, 95% CI 1.16-1.5). The substantial attenuation in risk after more comprehensive adjustment suggests that patients at higher risk of SH are likely at higher risk of ASCVD. Conclusions: In a large, diverse and contemporary cohort of patients with diabetes, SH as defined by hypoglycemia-related hospital utilization is associated with greater risk of ASCVD. Increased awareness in recognizing this risk and vigilance in care for this higher risk population is warranted.


2020 ◽  
Author(s):  
Natan Feter ◽  
Jayne S Leite ◽  
Daniel Umpierre ◽  
Eduardo L Caputo ◽  
Airton J Rombaldi

Abstract Background: We aimed to test which life course model best described the association between leisure-time physical activity (LTPA) and multimorbidity at age 55. We analyzed data from birth to age 55 using the database from the 1958 National Child Development Survey. Methods: Multimorbidity was considered as the presence of more than one chronic condition. LTPA was measured through questionnaires from 1965 (age 7) to 2013 (age 55), which were applied in eight different occasions. We compared the fit of a series of nested adjusted logistic regression models (representing either the critical, accumulation or sensitive period models) with a fully saturated model. Data were reported as odds ratio (OR) and 95% confidence interval (CI).Results: From the initial sample of 17,415 cohort members, 9,134 were interviewed in the latest sweep (49.2%). Men were more physically active than women at ages 11, 16, and 23 (p<0.001). LTPA every day in the week was more frequent in women than men in ages 33, 42, and 50 (p<0.001). The sensitive analysis revealed that LTPA during adolescence (OR: 0.72; 95% CI: 0.57, 0.92) and late adult life (OR: 0.71; 95%CI: 0.55, 0.91) have a stronger effect on the risk for multimorbidity at age 55 considering all other life stages in the model. Also, adolescence showed a critical independent effect on the risk for multimorbidity (OR: 0.74; 95%CI: 0.59, 0.92). No difference was found between those models. Conclusions: These data support the notion of a protective physical activity “legacy” at early ages of childhood against multimorbidity at older ages. We highlight the need for LTPA promotion through intervention tailored especially on schooling and older ages in order to reduce the burden of multimorbidity.


2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Neng Zhou ◽  
Dangmei Liu ◽  
Xiaowang Bao

Simple and rapid high-performance liquid chromatography methods were developed for the determination of berberine (BB) in various rat tissues so as to evaluate a P-gp inhibitor, glycyrrhetinic acid (GA), on BB’s oral bioavailability. Acetonitrile was used to extract BB from tissues and showed different extraction recoveries in diverse tissues. The intra- and interday precision and accuracy were less than 10%. Long-term stability, pre (post) -preparative stability, and freeze-thaw stability were evaluated, and the results showed it could meet the need of this study. The proposed methods were subsequently applied to investigate the possible drug-drug interaction of GA and BB in vivo from the aspect of tissue distribution. The results showed that no significant difference was found between the group of low dose and high dose at the same time point. The tissue distributions show a saturated model, i.e., the content of BB in tissue tends to be constant while its dose is more than 200 mg/kg. Besides, the contents of BB ranged from high to low according to the order of the liver, kidney, and spleen. The BB content in the liver is especially high as compared to other tissues.


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