Improved Spatial Modulation for High Spectral Efficiency

Spatial Modulation (SM) is a technique that can enhance the capacity of MIMO schemes by exploiting the index of transmit antenna to convey information bits. In this paper, we describe this technique, and present a new MIMO transmission scheme that combines SM and spatial multiplexing. In the basic form of SM, only one out of MT available antennas is selected for transmission in any given symbol interval. We propose to use more than one antenna to transmit several symbols simultaneously. This would increase the spectral efficiency. At the receiver, an optimal detector is employed to jointly estimate the transmitted symbols as well as the index of the active transmit antennas. In this paper we evaluate the performance of this scheme in an uncorrelated Rayleigh fading channel. The simulations results show that the proposed scheme outperforms the optimal SM and V-BLAST (Vertical Bell Laboratories Layered space-time at high signal-to-noise ratio (SNR). For example, if we seek a spectral efficiency of 8 bits/s/Hz at bit error rate (BER) of 10^-5, the proposed scheme provides 5dB and 7dB improvements over SM and V-BLAST, respectively.Comment: 7 pages, 4 figures, 1 table, International Journal of Distributed and Parallel Systems (IJDPS) Vol.3, No.2, March 201

Role of ankle-brachial pressure index as a predictor of coronary artery disease severity in diabetic and non-diabetic patients

PurposeThe aim of the study was to estimate the role of ankle-brachial pressure index (ABI) in predicting severity of coronary artery disease (CAD) in patients with or without diabetes mellitus.MethodsThis study included 120 patients with CAD proved by coronary angiography and ABI was measured for all of them. They were divided into 4 groups; Group (A): Non-diabetic patients without peripheral arterial disease (PAD) (ABI < or =0.9) , Group (B):diabetic patients without PAD (ABI < or =0.9), Group (C):Non-diabetic patients with PAD (ABI>0.9) and Group (D):diabetic patients with PAD (ABI>0.9).ResultsHypertension was more prevalent in group (D) (p value>0.05). Group (C) had the highest mean age and the highest percentage of smokers, after normalization of the effects of the risk factors mean Gensini score, mean number of affected coronary vessels, mean number of coronary artery lesions and the percentage of coronary artery chronic total occlusions (CTO) were significantly higher in groups (C & D) (p>0.001) (Table 1).ConclusionABI had a significant relationship with the degree of CAD severity. Therefore ABI seems to be a reliable independent prognostic marker of CAD severity in patients with or without diabetes mellitus

The Effect of Different Irrigant Activation Methods on Postoperative Pain After Endodontic Retreatment

Objective: This study was designed to evaluate the effect of different irrigant activation methods on post operative pain after endodontic retreatment. Materials and Methods : Seventy eight patients need non surgical retreatment in mandibular first molar were involved in the study. The retreatment was performed in two visits ,at first visit cases were randomly divided into three groups according to methods of irrigant activation after root canal retreatment with protaper next rotary Ni-TI system. Group A (n=26) Root canals were irrigated using 2.6% sodium hypochlorite (NaOCl) with manual dynamic agitation using master cone Group B (n=26) Root canals were irrigated using 2.6% sodium hypochlorite (NaOCl) using ultrasonic machine (ultra-x) for 60 seconds. Group C (n=26) Root canals were irrigated using 2.6% sodium hypochlorite (NaOCl) with NaviTip (29-gauge 27 mm) with double side tip. At second visit after one week, obturation was performed using modified single cone technique ans access cavity was filled with coronal restoration. After two visits root canal treatment and a specific method of agitation, depending on each group, the patients were given a questionnaire on which the patient would mark the degree of pain in a scale from 0 to 10 at 6, 12, 24, 48 72 hrs and one week post-obturation. Data were statistically analyzed with a significance level of P ≤0.05. Results: At 6,12,24 hrs, there was significant difference between the groups in pain intensity where control group C (Navitip with side vented needle) showed more pain scores than in the intervention groups (Ultra X and manual dynamic agitation). On the other hand, at 48, 72 hours and 7 days post- operative ,there was no statistically significant difference in pain among tested groups. Conclusion: Agitation of the irrigation is reliable safe to clinican and effective as final step irrigation protocol with successful management of postoperative pain in retreatment cases. The intensity of postoperative pain decreased with time regardless of final irrigation protocol used

Novel Urinary Biomarkers and Chronic Kidney Disease After Coronary Angiography: A Prospective Case-Controlled Study

BACKGROUND: Novel urinary biomarkers may have potential for early detection of acute kidney injury. AIM: The aim of the study was to test two urinary biomarkers: Kidney injury molecule-1(KIM-1) and liver-type fatty acid binding protein (L-FABP) as markers of kidney injury following coronary angiography. METHODS: This is a prospective non-randomized controlled trial, performed in two large teaching hospitals. Patients were recruited from the catheter lab or form nephrology outpatient clinics. In group (A), 100 patients with AKI on top of CKD after coronary angiography and Group B: Thirty-one patients with stable CKD as a control. KIM-1 and L-FABP were measured at base line and after 3 months. RESULTS: In group (A), 100 patients who had acute on top of CKD after coronary angiography, stage progression occurred in 15 patients in group (A) compared to two patients in group (B) (p = 0.28). The median change in eGFR after 3 months was not statistically significant between both groups (p = 0.8). Median baseline urinary liver-type fatty acid binding protein was higher in Group A compared to Group B (3.7 μg/g vs. 1.82μg/g). The change in L-FABP from baseline to 3 months was significant between both groups (p &lt; 0.001). The median urinary concentrations of KIM-1 and L-FABP were higher at the end of the follow-up compared to base line values in both groups, (p &lt; 0.000). CONCLUSION: Urinary L-FABP correlates with kidney function decline in patients with acute on top of CKD after coronary angiography. Urinary levels of KIM-1 and L-FABP at 3 months increase significantly compared to baseline in patients with progressive CKD

Efficacy of Mesenchymal Stem Cells in Suppression of Hepatocarcinorigenesis in Rats: Possible Role of Wnt Signaling

<p>Abstract</p> <p>Background</p> <p>The present study was conducted to evaluate the tumor suppressive effects of bone marrow derived mesenchymal stem cells (MSCs) in an experimental hepatocellular carcinoma (HCC) model in rats and to investigate the possible role of Wnt signaling in hepato-carcinogenesis.</p> <p>Methods</p> <p>Ninety rats were included in the study and were divided equally into: Control group, rats which received MSCs only, rats which received MSCs vehicle only, HCC group induced by diethylnitroseamine (DENA) and CCl_<b>4</b>, rats which received MSCs after HCC induction, rats which received MSCs before HCC induction. Histopathological examination and gene expression of Wnt signaling target genes by real time, reverse transcription-polymerase chain reaction (RT-PCR) in rat liver tissue, in addition to serum levels of ALT, AST and alpha fetoprotein were performed in all groups.</p> <p>Results</p> <p>Histopathological examination of liver tissue from animals which received DENA-CCl₄only, revealed the presence of anaplastic carcinoma cells and macro-regenerative nodules type II with foci of large and small cell dysplasia. Administration of MSCs into rats after induction of experimental HCC improved the histopathological picture which showed minimal liver cell damage, reversible changes, areas of cell drop out filled with stem cells. Gene expression in rat liver tissue demonstrated that MSCs downregulated <it>β-catenin</it>, proliferating cell nuclear antigen (<it>PCNA</it>), <it>cyclin D </it>and <it>survivin </it>genes expression in liver tissues after HCC induction. Amelioration of the liver status after administration of MSCs has been inferred by the significant decrease of ALT, AST and Alpha fetoprotein serum levels. Administration of MSCs before HCC induction did not show any tumor suppressive or protective effect.</p> <p>Conclusions</p> <p>Administration of MSCs in chemically induced HCC has tumor suppressive effects as evidenced by down regulation of Wnt signaling target genes concerned with antiapoptosis, mitogenesis, cell proliferation and cell cycle regulation, with subsequent amelioration of liver histopathological picture and liver function.</p

Speciation of common Gram-negative pathogens using a highly multiplexed high resolution melt curve assay

The identification of the bacterial species responsible for an infection remains an important step for the selection of antimicrobial therapy. Gram-negative bacteria are an important source of hospital and community acquired infections and frequently antimicrobial resistant. Speciation of bacteria is typically carried out by biochemical profiling of organisms isolated from clinical specimens, which is time consuming and delays the initiation of tailored treatment. Whilst molecular methods such as PCR have been used, they often struggle with the challenge of detecting and discriminating a wide range of targets. High resolution melt analysis is an end-point qPCR detection method that provides greater multiplexing capability than probe based methods. Here we report the design of a high resolution melt analysis assay for the identification of six common Gram-negative pathogens; Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Pseudomonas aeruginosa, Salmonella Sp, and Acinetobacter baumannii, and a generic Gram-negative specific 16S rRNA control. The assay was evaluated using a well characterised collection of 113 clinically isolated Gram-negative bacteria. The agreement between the HRM assay and the reference test of PCR and sequencing was 98.2% (Kappa 0.96); the overall sensitivity and specificity of the assay was 97.1% (95% CI: 90.1–99.7%) and 100% (95% CI: 91.78–100%) respectively