In service oriented computing, service providers and service requesters are main interacting entities. A service provider publishes the services it wishes to make public using service registries. A service requester initiates a discovery process to find the service that meets its requirements using the service registries. Current approaches for the publication and discovery do not realize the essential relationship between the service contract and the conditions in which the service can guarantee its contract. Moreover, they do not use any formal methods for specifying services, contracts, and compositions. Without a formal basis it is not possible to justify through a rigorous verification the correctness conditions for service compositions and the satisfaction of contractual obligations in service provisions. In our recent works, we have identified the role of contextual information, trustworthiness information and legal rules in service provision. This paper focuses on the publication and discovery of trustworthy context-dependent services as supported by the novel framework FrSeC. It introduces a novel ranking algorithm that ranks trustworthy context-dependent services according to the degree they match service requesters requirements. Finally, this paper introduces a prototype implementation for the matching and ranking of services as supported by FrSeC.

Background The overuse of short-acting β2-agonists (SABA) is associated with poor asthma control. However, data on SABA use in the Gulf region are limited. Herein, we describe SABA prescription practices and clinical outcomes in patients with asthma from the Gulf cohort of the SABA use IN Asthma (SABINA) III study. Methods In this cross-sectional study conducted at 16 sites across Kuwait, Oman, and the United Arab Emirates, eligible patients (aged ≥ 12 years) with asthma were classified based on investigator-defined disease severity guided by the 2017 Global Initiative for Asthma report and by practice type, i.e., respiratory specialist or primary care physician. Data on demographics, disease characteristics, and prescribed asthma treatments, including SABA, in the 12 months prior to a single, prospective, study visit were transcribed onto electronic case report forms (eCRFs). All analyses were descriptive in nature. Continuous variables were summarized by the number of non-missing values, given as mean (standard deviation [SD]) and median (range). Categorical variables were summarized by frequency counts and percentages. Results This study analyzed data from 301 patients with asthma, 54.5% of whom were treated by respiratory specialists. Most patients were female (61.8%), with a mean age of 43.9 years, and 84.4% were classified with moderate-to-severe disease, with a mean (SD) asthma duration of 14.8 (10.8) years. Asthma was partly controlled or uncontrolled in 51.2% of patients, with 41.9% experiencing ≥ 1 severe exacerbation in the 12 months preceding their study visit. Overall, 58.5% of patients were prescribed ≥ 3 SABA canisters, 19.3% were prescribed ≥ 10 canisters, and 13.3% purchased SABA over-the-counter (OTC) in the 12 months before the study visit. Most patients who purchased OTC SABA (92.5%) also received SABA prescriptions. Inhaled corticosteroid/long-acting β2-agonist combinations and oral corticosteroid bursts were prescribed to 87.7% and 22.6% of patients, respectively. Conclusions SABA over-prescription was highly prevalent in the Gulf region, compounded by purchases of nonprescription SABA and suboptimal asthma-related outcomes. Increased awareness among policymakers and healthcare practitioners is needed to ensure implementation of current, evidence-based, treatment recommendations to optimize asthma management in this region. Trial registration NCT03857178 (ClinicalTrials.gov).

Current approaches for the discovery, specification, and provision of services ignore the relationship between the service contract and the conditions in which the service can guarantee its contract. Moreover, they do not use formal methods for specifying services, contracts, and compositions. Without a formal basis it is not possible to justify through formal verification the correctness conditions for service compositions and the satisfaction of contractual obligations in service provisions. We remedy this situation in this paper. We present a formal definition of services with context-dependent contracts. We define a composition theory of services with context-dependent contracts taking into consideration functional, nonfunctional, legal and contextual information. Finally, we present a formal verification approach that transforms the formal specification of service composition into extended timed automata that can be verified using the model checking tool UPPAAL

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