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Acute respiratory distress syndrome in children with lower respiratory tract infection requiring invasive mechanical ventilation:post hoc analysis of the 2019-2020 bronchiolitis and codetection cohort
No full textObjectives: Bronchiolitis and other lower respiratory tract infections (LRTIs) are the most common causes of pediatric respiratory failure. There is insufficient evidence characterizing pediatric acute respiratory distress syndrome (PARDS) in young children with LRTI to inform clinical management. We aimed to describe the prevalence and clinical characteristics of children intubated for LRTI and meeting PARDS criteria.Design: We performed a post hoc analysis of data from the Bronchiolitis And COdetectioN (BACON) study, an international prospective observational study of critical bronchiolitis. We compared PARDS subjects (meeting criteria the first full calendar day following intubation) to non-PARDS subjects.Setting: Forty-eight international PICUs recruiting to the BACON study, from December 2019 to November 2020.Patients: Children younger than 2 years old, requiring mechanical ventilation for acute LRTI.Interventions: None.Measurements and Main Results: Complete data were available for 571 children. Day 1 PARDS was diagnosed in 240 subjects(42%) and associated with increased mortality (7.9% vs. 2.7%; p = 0.023), greater duration of invasive ventilation (165 hr [interquartile range, 112–251 hr] vs. 135 hr [76–204 hr]; p < 0.001), and PICU length of stay (11 d [7–16 d] vs. 8 d [5–13 d]; p < 0.001). In our multivariable competing risk model, the presence of PARDS on day 1 was causally related to a prolonged duration of mechanical ventilation with the probability of extubation at 7 days for those with PARDS equal to 49% (44–54%) compared with 64% (59–69%) for those without PARDS.Conclusions:PARDS development was common in this critical bronchiolitis cohort, resulted in a longer duration of mechanical ventilation, and was associated with increased mortality and PICU length of stay. Prospective studies are needed to elucidate the optimal management of critical bronchiolitis.</div
Understanding dynamic molecular responses is key to designing environmental stress experiments:a review of gene and protein expression in cnidaria under stress
No full textGene and protein expression analyses are powerful tools to investigate the responses of cnidarians to stress, providing information on both genetic and functional variation and capturing dynamic shifts in organismal physiology. As the use of high throughput sequencing to understand responses of cnidarians to stressors is still relatively new, standard experimental protocols have not yet been established, which limits the ability to compare studies. We (1) systematically reviewed the literature of cnidarian gene and protein expression studies related to environmental stressors to determine how the laboratory experiments were designed and (2) investigated the consistency in responses of genes commonly used as biomarkers within stress experiments conducted on the five most-studied cnidarian genera. Duration of exposure to the stressor, acclimation period and intensity of stress varied greatly among experiments, and most studies did not sample during acclimation and recovery. Before designing experiments that aim to characterise molecular responses to a specific environmental stress, research efforts need to focus on understanding the plasticity of whole transcriptome responses, as gene expression can vary under different stress intensities and durations of exposure. Additionally, only seven genes that were tested in at least two different genera showed a consistent response under heat stress (CuZn-SOD, c-type lectin, FGFR1, MMP, Zn-MP, NF-κB and SLC26). These genes have the potential to standardise evaluations of temperature stress across experiments on cnidarians, and we suggest exploring their use as general cnidarian biomarkers of temperature stress (cBATS).</p
Projection algebras and free projection- and idempotent-generated regular ∗-semigroups
No full textThe purpose of this paper is to introduce a new family of semigroups—the free projection-generated regular ∗- semigroups -and initiate their systematic study. Such a semigroup PG(P) is constructed from a projection algebra P, using the recent groupoid approach to regular ∗-semigroups. The assignment P → PG(P) is a left adjoint to the forgetful functor that maps a regular ∗-semigroup S to its projection algebra P(S). In fact, the category of projection algebras is coreflective in the category of regular ∗-semigroups. The algebra P(S) uniquely determines the biordered structure of the idempotents E(S), up to isomorphism, and this leads to a category equivalence between projection algebras and regular ∗-biordered sets. As a consequence, PG(P) can be viewed as a quotient of the classical free idempotent-generated (regular) semigroups IG(E) and RIG(E), where E = E(PG(P)); this is witnessed by a number of presentations in terms of generators and defining relations. The semigroup PG(P) can also be interpreted topologically, through a natural link to the fundamental groupoid of a simplicial complex explicitly constructed from P. The above theory is illustrated on a number of examples. In one direction, the free construction applied to the projection algebras of adjacency semigroups yields a new family of graph-based path semigroups. In another, it turns out that, remarkably, the Temperley–Lieb monoid ℒn is the free regular ∗-semigroup over its own projection algebra P(ℒn)
Liberal pluralism, postliberal genealogies and theological history
No full textThe postliberal genealogies of John Milbank, Brad Gregory, and Patrick Deneen refuse to disaggregate liberalism and thus denounce it wholesale. Likewise, these narratives are not sufficiently ambivalent in describing both modern liberalism and pre-modern politics. I respond to these narratives by disaggregating liberalism into various forms. I note how a certain version of political liberalism, rooted in the freedom of conscience, has important precedents in pre-modern Christianity. In view of this, I defend the plausibility of a historical interpretation positing a more positive, yet nonetheless ambivalent relation between important trends in Christianity and versions of modern liberalism, thereby calling into question the indiscriminate denunciation of liberalism posited as the ‘moral’ of these postliberal narratives
Sectarianism and civil war in Syria
No full textThis study describes and explains sectarianization in Syria before and after the Arab uprising. As an epicentre of sectarian conflict, Syria provides an excellent laboratory for its study. This study compares variance in Syria’s sectarianism over time and across place on order to expose its causes and its varying impact on Syria’s society and polity. The introductory chapter examines key approaches to and debates over sectarianism in the Syrian uprising from which is derived a framework of analysis. Subsequent empirical chapters are divided into two sections. Several examine ley aspects of sectarianism at the national level, looking at the interaction of sectarianism and state formation over the long term; the impact of the regional power struggle on Syria’s sectarianization; and whether sectarianism was institutionalized by civil war governance in both regime- and opposition-controlled areas. A second set of chapters looks at sectarianism in Syria’s different cities, regions and communities, from Damascus, Homs, Hama, and Aleppo to Idlib, the Alawi coast, and the Druze and Christian communities. The concluding chapter uses the analytical framework to systematically compare the evidence from the empirical cases in order to identify regularities. This not only provides nuanced insights into the Syrian case but also informs broader theoretical discussions of sectarianism
Identity and state building over time:political institutions and Syria’s sectarianism-nationalism balance
No full textThis chapter examines the interaction of Syria’s multi-sectarian identity heritage and varying regime types or political institutional configurations. These have, over time co-constituted each other, interacting in a circular form in which identity affects the institutional design of the state and the latter affects the former. We test the institutionalist approach that charts how political institutions can help produce, reproduce or transform identities, depending on their design and strength; conversely, variations in identity are likely to affect the kinds of institutions that can be created. This approach is deployed to track the Syrian trajectory from independence thru the Uprising, paying special attention to how big differences in governance (liberal oligarchy; authoritarian populist, authoritarian post-populist) have interacted to mute or reproduce sectarianism
Collective entrepreneurship and cooperatives principles:configurations for achieving social and economic goals in cooperatives
No full textCooperatives, particularly those comprising small- and medium-sized enterprises, are crucial in collective entrepreneurship due to their blend of social and economic goals. Mainstream management research often overlooks cooperatives, deeming member-based ownership arrangements as limiting competitiveness. This study uses data from 68 New Zealand cooperatives to examine how different configurations of cooperative principles and knowledge-sharing practices affect entrepreneurial orientation. First, we challenge the notion of the degeneration thesis, which assumes that cooperatives must sacrifice economic performance for social missions. Second, we show that not all principles are equal. By identifying multiple successful configurations of cooperative principles, we show that adherence to cooperative principles is dynamic and contingent on the cooperative’s competitive strategy. Third, our findings highlight the necessity of knowledge sharing to complement the principles and to achieve such competitive strategies. Taken together, we contribute to ongoing discussions about sustainable organisational forms and collective entrepreneurship by highlighting the value of the cooperative form
Can pruning improve agent-based models' calibration? An application to HPVsim
No full textAgent-Based Models (ABMs) have gained popularity over the COVID-19 epidemic, but their efficient calibration remains challenging. Here we propose a novel calibration architecture by investigating the role of pruning in ABM calibration. We use a recently developed model for human papillomavirus (HPV) transmission and focus on its integrated calibration framework, Optuna. Simulating six synthetic datasets of various temporal skewness, with six pruners, we show that more aggressive pruners perform best (in terms of loss function at end of calibration) for very-back-heavy datasets, while median pruners are better for more-front-heavy datasets. For more balanced datasets most of the pruners perform similarly to no pruning. However, across all datasets pruning notably sped up calibration, in many cases without compromising on - or even improving upon - the optimal found parameter set. We validate our results through application to real-life data. Finally, we discuss approaches for improving “bad pruners” for balanced datasets. Our proof-of-principle study shows that pruners can improve ABMs’ calibration. As ABMs are becoming more widely used in epidemiological modelling, designing the next level of pandemic preparedness strategies will need to address efficient calibration; we believe pruning is a cornerstone for this