9 research outputs found

    Cloud Services Brokerage for Mobile Ubiquitous Computing

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    Recently, companies are adopting Mobile Cloud Computing (MCC) to efficiently deliver enterprise services to users (or consumers) on their personalized devices. MCC is the facilitation of mobile devices (e.g., smartphones, tablets, notebooks, and smart watches) to access virtualized services such as software applications, servers, storage, and network services over the Internet. With the advancement and diversity of the mobile landscape, there has been a growing trend in consumer attitude where a single user owns multiple mobile devices. This paradigm of supporting a single user or consumer to access multiple services from n-devices is referred to as the Ubiquitous Cloud Computing (UCC) or the Personal Cloud Computing. In the UCC era, consumers expect to have application and data consistency across their multiple devices and in real time. However, this expectation can be hindered by the intermittent loss of connectivity in wireless networks, user mobility, and peak load demands. Hence, this dissertation presents an architectural framework called, Cloud Services Brokerage for Mobile Ubiquitous Cloud Computing (CSB-UCC), which ensures soft real-time and reliable services consumption on multiple devices of users. The CSB-UCC acts as an application middleware broker that connects the n-devices of users to the multi-cloud services. The designed system determines the multi-cloud services based on the user's subscriptions and the n-devices are determined through device registration on the broker. The preliminary evaluations of the designed system shows that the following are achieved: 1) high scalability through the adoption of a distributed architecture of the brokerage service, 2) providing soft real-time application synchronization for consistent user experience through an enhanced mobile-to-cloud proximity-based access technique, 3) reliable error recovery from system failure through transactional services re-assignment to active nodes, and 4) transparent audit trail through access-level and context-centric provenance

    ENABLING MOBILE DEVICES TO HOST CONSUMERS AND PROVIDERS OF RESTFUL WEB SERVICES

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    The strong growth in the use of mobile devices such as smartphones and tablets in Enterprise Information Systems has led to growing research in the area of mobile Web services. Web services are applications that are developed based on network standards such as Services Oriented Architecture and Representational State Transfer (REST). The mobile research community mostly focused on facilitating the mobile devices as client consumers especially in heterogeneous Web services. However, with the advancement in mobile device capabilities in terms of processing power and storage, this thesis seeks to utilize these devices as hosts of REST Web services. In order to host services on mobile devices, some key challenges have to be addressed. Since data and services accessibility is facilitated by the mobile devices which communicate via unstable wireless networks, the challenges of network latency and synchronization of data (i.e. the Web resources) among the mobile participants must be addressed. To address these challenges, this thesis proposes a cloud-based middleware that enables reliable communication between the mobile hosts in unreliable Wi-Fi networks. The middleware employs techniques such as message routing and Web resources state changes detection in order to push data to the mobile participants in real time. Additionally, to ensure high availability of data, the proposed middleware has a cache component which stores the replicas of the mobile hosts’ Web resources. As a result, in case a mobile host is disconnected, the Web resources of the host can be accessed on the middleware. The key contributions of this thesis are the identification of mobile devices as hosts of RESTful Web services and the implementation of middleware frameworks that support mobile communication in unreliable networks

    Strabismus and Amblyopia in Africa – A Systematic Review and Meta-Analysis

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    The objective of this review was to estimate the prevalence of strabismus and amblyopia in Africa. A systematic online literature search was conducted for articles on strabismus and amblyopia in Africa. Meta-analysis was performed, using the Freeman-Tukey double arcsine transformation, to estimate the prevalence of strabismus and amblyopia in Africa. Subgroup analyses were conducted according to age, gender, study year, and type of amblyopia. Meta-regression was used to evaluate the influence of predetermined factors on the prevalence of amblyopia. 8 (1 population-based & 7 school-based) and 21 (3 population-based & 18 school-based) studies on strabismus and amblyopia with sample sizes of 22,355 and 46,841, respectively, were included in the review. Overall prevalence of strabismus in Africa was estimated to be 0.8% (95% CI: 0.4% − 1.4%); exotropia was 0.2% (95% CI: 0.1% − 0.5%) and esotropia was 0.5% (95% CI: 0.1% − 1.2%). Overall prevalence of amblyopia was estimated to be 0.6% (95% CI: 0.3% − 0.9%); refractive and strabismic amblyopia were 1.1% (95% CI: 0.2% − 2.5%) and 0.4% (95% CI: 0.2% − 0.6%), respectively. Prevalence estimate of amblyopia in males was 1.8% (95% CI: 0.7% − 3.3%) and in females was 1.3% (95% CI: 0.4% − 2.6%). There was a significant association between the prevalence of amblyopia and the type of amblyopia (p = .007) and the study year (p = .006). Although there appears to be a relatively low prevalence of strabismus and amblyopia in Africa, there is a dearth of well-designed populationbased studies on strabismus and amblyopia in Africa, resulting in the lack of epidemiological information on strabismus and amblyopia within the general African population. Information about the prevalence of strabismus and amblyopia across Africa can inform policy making and design and implementation of public health intervention program

    Enhancing Privacy in Wearable IoT through a Provenance Architecture

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    The Internet of Things (IoT) is inspired by network interconnectedness of humans, objects, and cloud services to facilitate new use cases and new business models across multiple enterprise domains including healthcare. This creates the need for continuous data streaming in IoT architectures which are mainly designed following the broadcast model. The model facilitates IoT devices to sense and deliver information to other nodes (e.g., cloud, physical objects, etc.) that are interested in the information. However, this is a recipe for privacy breaches since sensitive data, such as personal vitals from wearables, can be delivered to undesired sniffing nodes. In order to protect users’ privacy and manufacturers’ IP, as well as detecting and blocking malicious activity, this research paper proposes privacy-oriented IoT architecture following the provenance technique. This ensures that the IoT data will only be delivered to the nodes that subscribe to receive the information. Using the provenance technique to ensure high transparency, the work is able to provide trace routes for digital audit trail. Several empirical evaluations are conducted in a real-world wearable IoT ecosystem to prove the superiority of the proposed work

    Clinical factors influencing knowledge and self‐care practice among adults with type 2 diabetes mellitus

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    Abstract Aim The objective of the study was to determine the clinical factors associated with knowledge and self‐care practice among adults living with type 2 diabetes mellitus. Design Descriptive cross‐sectional design. Methods A convenience sample of 330 participants was recruited over 3‐months in 2018 and data were collected using a structured instrument. Results Participants on insulin treatment modality had four times higher odds of knowledge on diabetes (B = 4.17, p = 0.023) while those on combined therapy (both oral hypoglycaemic agent and insulin) had 7.26 times higher odds of knowledge (B = 7.26, p < 0.001). Participants without medically confirmed diabetic complications had 3.66 higher odds of knowledge of diabetes (B = 3.66, p = 0.002). Participants on insulin treatment modality had a 1.4‐fold higher odds of self‐care practice (B = 1.4, p = 0.028). It was revealed that participants with hypertension and diabetic foot had lower odds of self‐care practice (B = −1.13, p = 0.021). Conclusion In particular, participants who were on insulin and combined therapy (tablet and insulin) had higher knowledge and better self‐care practice. Self‐care was significantly influenced among those with, than those without diabetic foot and hypertension as complications

    Higher serum concentrations of vimentin and DAKP1 are associated with aggressive breast tumour phenotypes in Ghanaian women

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    Breast cancer, the most commonly diagnosed cancer among women and leading cause of cancer-related deaths worldwide, exhibits aggressive behavior in indigenous African women evidenced by high histologic grade tumours with low hormone receptor positivity. Aggressive breast cancers grow quickly, easily metastasize and recur and often have unfavourable outcomes. The current study investigated candidate genes that may regulate tumour aggression in Ghanaian women. We hypothesize that increased expression and function of certain genes other than the widely-held view attributing breast cancer aggression in African populations to their younger population age may be responsible for the aggressive nature of tumours. Employing ELISA, we assayed for vimentin and death-associated protein kinase 1 (DAPK1) from thawed archived (stored at -80 °C) serum samples obtained from 40 clinically confirmed Ghanaian breast cancer patients and 40 apparently healthy controls. Patients' clinical records and tumour parameters matching the samples were retrieved from the database of the hospital. ANOVA was used to compare means of serum protein concentration among groups while Chi-square analysis was used for the categorical data sets with p-value ≀0.05 considered significant. Multiple logistic regression analysis was conducted to determine the association between protein concentration and tumour parameters. Of the 80 samples, 27 (33.8%) and 53 (66.2%) were from young ( <35 years) and old (≄35 years), respectively. Vimentin and DAPK1 concentration were higher in patients than controls with higher levels in "young" age group than "old" age group. Vimentin concentration was highest in grade 3 tumours followed by grade 2 and 1 but that for DAPK1 was not significant. For vimentin, tumour area strongly correlated with tumour grade (r = 0.696, p < 0.05) but weakly correlated with tumour stage (r = 0.420, p < 0.05). Patient's age correlated with DAPK1 concentration (r = 0.393, p < 0.05). DAPK1 serum levels weakly correlated with cancer duration (r = 0.098, p = 0.27) and tumour size (r = 0.40, p < 0.05). Serum concentration of Vimentin and DAPK1 are elevated in Ghanaian breast cancer patients. This may be partly responsible for aggressive nature of the disease among the population. Vimentin and DAPK1 should be explored further as potential breast cancer biomarkers in African

    Comparative efficacy of low-dose versus standard-dose azithromycin for patients with yaws: a randomised non-inferiority trial in Ghana and Papua New Guinea

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    Summary: Background: A dose of 30 mg/kg of azithromycin is recommended for treatment of yaws, a disease targeted for global eradication. Treatment with 20 mg/kg of azithromycin is recommended for the elimination of trachoma as a public health problem. In some settings, these diseases are co-endemic. We aimed to determine the efficacy of 20 mg/kg of azithromycin compared with 30 mg/kg azithromycin for the treatment of active and latent yaws. Methods: We did a non-inferiority, open-label, randomised controlled trial in children aged 6–15 years who were recruited from schools in Ghana and schools and the community in Papua New Guinea. Participants were enrolled based on the presence of a clinical lesion that was consistent with infectious primary or secondary yaws and a positive rapid diagnostic test for treponemal and non-treponemal antibodies. Participants were randomly assigned (1:1) to receive either standard-dose (30 mg/kg) or low-dose (20 mg/kg) azithromycin by a computer-generated random number sequence. Health-care workers assessing clinical outcomes in the field were not blinded to the patient's treatment, but investigators involved in statistical or laboratory analyses and the participants were blinded to treatment group. We followed up participants at 4 weeks and 6 months. The primary outcome was cure at 6 months, defined as lesion healing at 4 weeks in patients with active yaws and at least a four-fold decrease in rapid plasma reagin titre from baseline to 6 months in patients with active and latent yaws. Active yaws was defined as a skin lesion that was positive for Treponema pallidum ssp pertenue in PCR testing. We used a non-inferiority margin of 10%. This trial was registered with ClinicalTrials.gov, number NCT02344628. Findings: Between June 12, 2015, and July 2, 2016, 583 (65·1%) of 895 children screened were enrolled; 292 patients were assigned a low dose of azithromycin and 291 patients were assigned a standard dose of azithromycin. 191 participants had active yaws and 392 had presumed latent yaws. Complete follow-up to 6 months was available for 157 (82·2%) of 191 patients with active yaws. In cases of active yaws, cure was achieved in 61 (80·3%) of 76 patients in the low-dose group and in 68 (84·0%) of 81 patients in the standard-dose group (difference 3·7%; 95% CI −8·4 to 15·7%; this result did not meet the non-inferiority criterion). There were no serious adverse events reported in response to treatment in either group. The most commonly reported adverse event at 4 weeks was gastrointestinal upset, with eight (2·7%) participants in each group reporting this symptom. Interpretation: In this study, low-dose azithromycin did not meet the prespecified non-inferiority margin compared with standard-dose azithromycin in achieving clinical and serological cure in PCR-confirmed active yaws. Only a single participant (with presumed latent yaws) had definitive serological failure. This work suggests that 20 mg/kg of azithromycin is probably effective against yaws, but further data are needed. Funding: Coalition for Operational Research on Neglected Tropical Diseases
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