Self-organising comprehensive handover strategy for multi-tier LTE-advanced heterogeneous networks

Long term evolution (LTE)-advanced was introduced as real fourth generation (4G) with its new features and additional functions, satisfying the growing demands of quality and network coverage for the network operators' subscribers. The term muti-tier has also been recently used with respect to the heterogeneity of the network by applying the various subnetwork cooperative systems and functionalities with self-organising capabilities. Using indoor short-range low-power cellular base stations, for example, femtocells, in cooperation with existing long-range macrocells are considered as the key technical challenge of this multi-tier configuration. Furthermore, shortage of network spectrum is a major concern for network operators which forces them to spend additional attentions to overcome the degradation in performance and quality of services in 4G HetNets. This study investigates handover between the different layers of a heterogeneous LTE-advanced system, as a critical attribute to plan the best way of interactive coordination within the network for the proposed HetNet. The proposed comprehensive handover algorithm takes multiple factors in both handover sensing and decision stages, based on signal power reception, resource availability and handover optimisation, as well as prioritisation among macro and femto stations, to obtain maximum signal quality while avoiding unnecessary handovers

Co-infections and antimicrobial resistance profile of Mycobacterium tuberculosis and Streptococcus pneumoniae among patients with pulmonary infections attending tertiary health facilities in Makurdi, Nigeria

Background: Pulmonary infections (Pls) cause mortality in elderly patients that have co-morbidities. These infections are life-threatening in the younger population, especially in infants and children. Co-infection with Mycobacterium tuberculosis and Streptococcus pneumoniae occurring concurrently may lead to undiagnosed Streptococcus pneumoniae leading to inadequate treatment. Aim: The study investigates the co-infection and antimicrobial resistance profile of Mycobacterium tuberculosis and Streptococcus pneumoniae in Makurdi, Nigeria. Materials and methods:  A total of 273 sputum samples were collected from patients with pulmonary infection attending chest clinics in tertiary health institutions in Makurdi and analysed. Genexpert was used for Mycobacterium tuberculosis while Streptococcus pneumoniae isolates were identified using Gram-staining reaction, optochin and bile solubility tests. The susceptibility test for Streptococcus pneumoniae was performed using Kirby-Bauer method. Results: Out of the 273 sputum samples, the percentage occurrence of mono-infections with Mycobacterium tuberculosis was 14(5.13%) while that with rifampicin resistance was 1(0.37%). The occurrence of mono-infection with Streptococcus pneumoniae was 11(4.03%). The resistance profile showed trimethoprim/sulphamethoxazole (septrin) with the highest resistance 6(54.55%) and vancomycin 5(45.45%) while amoxicillin/clavulanic acid and ceftriaxone had zero resistance (0.0%). There was the occurrence of co-infections in 3(1.10%) out of the 273 patients sampled. There was no significant association (p > 0.05) between Mycobacterium tuberculosis, Streptococcus pneumoniae, their co-infections and the variables analyzed. Conclusion: The occurrence rate of Streptococcus pneumoniae and Mycobacterium tuberculosis co-infections is low among suspected pulmonary infection cases with an occurrence rate of 1.10%. Early detection and proper management of co-infections are recommended

Visceral Adiposity, Genetic Susceptibility, and Risk of Complications Among Individuals with Crohn's Disease

Introduction: Adipose tissue in mesenteric fat plays a key role in systemic and luminal inflammation. However, little is known about the role of visceral adipose tissue (VAT) and its interaction with genetic predisposition in Crohn's disease (CD) progression. Methods: Our study population included patients with CD enrolled in Prospective Registry in Inflammatory Bowel Disease Study at Massachusetts General Hospital (PRISM). VAT volume was measured from computed tomography using Aquarius 3D. We used logistic regression models to estimate the multivariable-adjusted odds ratio and 95% CI. We tested for effect modification by genetic predisposition using the log likelihood ratio test. Results: Among 482 patients with CD with available data on VAT, 174 developed penetrating disease, 132 developed stricturing disease, 147 developed perianal disease, and 252 required surgery. Compared with individuals in the lowest quartile of VAT volume, the multivariable-adjusted odds ratio of surgery among individuals in the highest quartile was 2.02 (95% CI, 1.09-3.76; P-trend = 0.006). Similarly, the risk of penetrating disease seemed to increase with greater VAT volume (P-trend = 0.022) but not stricturing or perianal disease (all P-trend > 0.23). The associations between VAT volume and CD complications were not modified by genetic predisposition (all P-interaction > 0.12). Conclusions: Visceral adiposity as measured by VAT volume may be associated with a significant increase in the risk of penetrating disease and surgery in CD. Our data suggest that visceral adiposity as measured by VAT may negatively impact long-term progression of CD regardless of genetic predisposition