A reusable observer pattern implementation using package templates

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Sex differences in post-acute neurological sequelae of SARS-CoV-2 and symptom resolution in adults after COVID-19 hospitalization: an international multicenter prospective observational study

Although it is known that coronavirus disease 2019 can present with a range of neurological manifestations and in-hospital complications, sparse data exist on whether these initial neurological symptoms of coronavirus disease 2019 are closely associated with post-acute neurological sequelae of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2; PANSC) and whether female versus male sex impacts symptom resolution. In this international, multi-centre, prospective, observational study across 407 sites from 15 countries (30 January 2020 to 30 April 2022), we report the prevalence and risk factors of PANSC among hospitalized adults and investigate the differences between males and females on neurological symptom resolution over time. PANSC symptoms included altered consciousness/confusion, fatigue/malaise, anosmia, dysgeusia and muscle ache/joint pain, on which information was collected at index hospitalization and during follow-up assessments. The analysis considered a time to the resolution of individual and all neurological symptoms. The resulting times were modelled by Weibull regression, assuming mixed-case interval censoring, with sex and age included as covariates. The model results were summarized as cumulative probability functions and age-adjusted and sex-adjusted median times to resolution. We included 6862 hospitalized adults with coronavirus disease 2019, who had follow-up assessments. The median age of the participants was 57 years (39.2% females). Males and females had similar baseline characteristics, except that more males (versus females) were admitted to the intensive care unit (30.5 versus 20.3%) and received mechanical ventilation (17.2 versus 11.8%). Approximately 70% of patients had multiple neurological symptoms at the first follow-up (median = 102 days). Fatigue (49.9%) and myalgia/arthralgia (45.2%) were the most prevalent symptoms of PANSC at the initial follow-up. The reported prevalence in females was generally higher (versus males) for all symptoms. At 12 months, anosmia and dysgeusia were resolved in most patients, although fatigue, altered consciousness and myalgia remained unresolved in >10% of the cohort. Females had a longer time to the resolution (5.2 versus 3.4 months) of neurological symptoms at follow-up for those with more than one neurological symptom. In the multivariable analysis, males were associated with a shorter time to the resolution of symptoms (hazard ratio = 1.53; 95% confidence interval = 1.39–1.69). Intensive care unit admission was associated with a longer time to the resolution of symptoms (hazard ratio = 0.68; 95% confidence interval = 0.60–0.77). Post-discharge stroke was uncommon (0.3% in females and 0.5% in males). Despite the methodological challenges involved in the collection of survey data, this international multi-centre prospective cohort study demonstrated that PANSC following index hospitalization was high. Symptom prevalence was higher and took longer to resolve in females than in males. This supported the fact that while males were sicker during acute illness, females were disproportionately affected by PANSC

S.: Reuse and combination with package templates

ABSTRACT Package Templates (PT) is a mechanism for writing modules meant for reuse, where each module (template) consists of a collection of classes. Such a template must be instantiated in a program (at compile time) to form a set of ordinary classes, and during instantiation the classes may be adjusted with renaming and additional attributes. Package templates can be instantiated multiple times in the same program, each time with different adjustments and each time resulting in a fully independent set of classes. During instantiations, classes from two or more templates may be combined so that they get a new shared type with the properties from all the classes. This paper presents and discusses two proposed extensions to PT. The first has to do with the fact that PT naturally gets two variants of the "super" concept, where one is for ordinary superclasses, and the other is for the additions made to classes during instantiation. The second extension has to do with allowing templates to instantiate templates that are later to be specified

A run-time environment for concurrent ob jects with asynchronous method calls

AbstractA distributed system may be modeled by objects that run concurrently, each with its own processor, and communicate by remote method calls. However objects may have to wait for response to external calls; which can lead to inefficient use of processor capacity or even to deadlock. This paper addresses this limitation by means of asynchronous method calls and conditional processor release points. Although at the cost of additional internal nondeterminism in the objects, this approach seems attractive in asynchronous or unreliable distributed environments. The concepts are illustrated by the small object-oriented language Creol and its operational semantics, which is defined using rewriting logic as a semantic framework. Thus, Creol specifications may be executed with Maude as a language interpreter, which allows an incremental development of the language constructs and their operational semantics supported by testing in Maude. However, for prototyping of highly nondeterministic systems, Maude's deterministic engine may be a limitation to practical testing. To overcome this problem, a rewrite strategy based on a pseudo-random number generator is proposed, providing Maude with nondeterministic behavior