ABSTRACT
Digital security as a service is a crucial aspect as it deals with user privacy provision and secure content delivery to legitimate users. Most social media platforms utilize end-to-end encryption as a significant security feature. However, multimedia data transmission in group communication is not encrypted. One of the most important objectives for a service provider is to send the desired multimedia data/service to only legitimate subscriber. Broadcast encryption is the most appropriate cryptographic primitive solution for this problem. Therefore, this study devised a construction called anonymous revocable identity-based broadcast encryption that preserves the privacy of messages broadcasted and the identity of legitimate users, where even revoked users cannot extract information about the user's identity and sent data. The update key is broadcast periodically to non-revoked users, who can obtain the message using the update and decryption keys. A third-party can also revoke the users. It is proven that the proposed construction is semantically secure against IND-ID-CPA attacks and efficient in terms of computational cost and communication bandwidth.
Subject(s)
Privacy , Social Media , Humans , Computer Security , Algorithms , Information DisseminationABSTRACT
The recent advent of cloud computing provides a flexible way to effectively share data among multiple users. Cloud computing and cryptographic primitives are changing the way of healthcare unprecedentedly by providing real-time data sharing cost-effectively. Sharing various data items from different users to multiple sets of legitimate subscribers in the cloud environment is a challenging issue. The online electronic healthcare system requires multiple data items to be shared by different users for various purposes. In the present scenario, COVID-19 data is sensitive and must be encrypted to ensure data privacy. Secure sharing of such information is crucial. The standard broadcast encryption system is inefficient for this purpose. Multichannel broadcast encryption is a mechanism that enables secure sharing of different messages to different set of users efficiently. We propose an efficient and secure data sharing method with shorter ciphertext in public key setting using asymmetric (Type-III) pairings. The Type-III setting is the most efficient form among all pairing types regarding operations required and security. The semantic security of this method is proven under decisional BDHE complexity assumption without random oracle model.
Subject(s)
COVID-19 , Computer Security , Cloud Computing , Delivery of Health Care , Humans , Information DisseminationABSTRACT
A retrospective case-case control study was conducted, including 60 cases with daptomycin-nonsusceptible vancomycin-resistant enterococci (DNS-VRE) matched to cases with daptomycin-susceptible VRE and to uninfected controls (1â¶1â¶3 ratio). Immunosuppression, presence of comorbid conditions, and prior exposure to antimicrobials were independent predictors of DNS-VRE, although prior daptomycin exposure occurred rarely. In summary, a case-case control study identified independent risk factors for the isolation of DNS-VRE: immunosuppression, multiple comorbid conditions, and prior exposures to cephalosporines and metronidazole.
Subject(s)
Anti-Bacterial Agents/pharmacology , Daptomycin/pharmacology , Drug Resistance, Multiple, Bacterial , Enterococcus faecalis/drug effects , Enterococcus faecium/drug effects , Gram-Positive Bacterial Infections/epidemiology , Vancomycin/pharmacology , Adult , Aged , Case-Control Studies , Cephalosporins/therapeutic use , Comorbidity , Female , Gram-Positive Bacterial Infections/microbiology , Humans , Immunosuppression Therapy , Male , Metronidazole/therapeutic use , Middle Aged , Proportional Hazards Models , Retrospective Studies , Risk Factors , Statistics, Nonparametric , Vancomycin ResistanceABSTRACT
In published studies, cohorts of patients with bacteremia due to vancomycin-resistant Enterococcus (VRE) have predominantly been infected with Enterococcus faecium. Little is known about the epidemiology and outcomes associated with bacteremia due to VR Enterococcus faecalis. A retrospective study of isolates obtained from January 2008 to October 2010 was conducted at Detroit Medical Center (DMC). Unique patients with blood cultures positive for VRE were reviewed. Outcomes were analyzed using logistic regression. During the study period, 105 cases of bacteremia due to VR E. faecalis and 197 cases of bacteremia due to VR E. faecium were identified. The mean age in the study cohort was 61.5 ± 15 years; 162 subjects (53.6%) were male. After controlling for a propensity score, bacteremia due to VR E. faecalis was associated with >2-fold-lower in-hospital mortality than bacteremia due to VR E. faecium. Interestingly, bacteremia due to VR E. faecalis was associated with longer hospital stay after VRE isolation, although total length of stay was similar for groups with VR E. faecalis and VR E. faecium. Bacteremia due to VR E. faecalis was associated with a >2-fold-lower risk for mortality than bacteremia due to VR E. faecium, possibly due to the availability of ß-lactam therapeutics for treatment of VR E. faecalis.
