285 research outputs found

    Seismic Microzonation of Central Khartoum, Sudan

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    A preliminary seismic microzonation of Central Khartoum, Sudan is proposed. Khartoum, the capital of Sudan, is located at the confluence of White and Blue Niles. The city is heavily populated. The Central Khartoum with its high rise buildings is the center of governmental and business activities and is located on strip adjacent to the Blue Nile. Geological and geotechnical data indicated that the subsoil conditions at Central Khartoum are characterized by alluvial deposits underlain by Nubian Sandstone below a depth of 20 m. The alluvial deposits locally known as Gezira formations, consist of clays grading into silt and sand with depth. Macro seismic zonation of Sudan and its vicinities, developed by the authors, gave the ground acceleration at the bed rock surface. The effect of alluvial deposits at Central Khartoum on propagation of seismic motion parameters to the ground surface is investigated in this study. Correlations are proposed for pertinent cyclic soil properties such as shear modulus, damping, and shear wave velocity. The classical shear beam model developed by Idriss and Seed is used to study the effect of local soil conditions on ground motion parameters. In absence of strong motion records, artificial time histories of ground motion parameters are used. Plots showing the time histories of ground motion parameters at the ground surface are obtained. The results indicated amplification of ground acceleration of up to 1.15. Because of the presence of saturated loose to medium dense sand at some locations within Central Khartoum, the risk of earthquake-induced liquefaction is evaluated. The susceplity of subsoils in Central Khartoum to liguefaction is evaluated probabilistically by modifying the classical method developed by Seed and Idriss. The risk of earthquake-induced liquefaction is computed by combining the seismic hazard and the conditional probability of liquefaction. The study showed that the risk of liquefaction is low

    Scoring system to facilitate diagnosis of Gaucher disease

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    Background: Gaucher disease (GD) manifests heterogeneously and other conditions are often misdiagnosed in its place, leading to diagnostic delays. The Gaucher Earlier Diagnosis Consensus (GED‐C) initiative proposed a point‐scoring system (PSS) based on the signs and covariables that are most indicative of GD to help clinicians identify which individuals to test for GD. Aims: To validate the PSS retrospectively in a test population including patients with GD and other conditions with overlapping manifestations. Methods: Four cohorts of adults with GD, liver disease (LD), haematological malignancy (HM) or immune thrombocytopenia were identified from hospital records. Clinical data were audited for GED‐C factors identified as potentially indicative of GD and aggregate scores calculated (sum of scores/number of factors) based on published PSS weightings. Threshold discriminatory PSS scores, sensitivity and specificity were determined by receiver‐operating characteristic (ROC) analysis. Results: Among 100 patients (GD, n = 25; non‐GD, n = 75), analyses based on 11 possible factors estimated group mean (standard deviation) PSS scores of: GD (n = 14), 1.08 (0.25); non‐GD (n = 38), 0.58 (0.31). Mean between‐group difference (95% confidence interval (CI)) was (−0.49 (−0.68, −0.31)) and area under the ROC analysis curve (95% CI) was 0.88 (0.78, 0.97). A threshold PSS score of 0.82 identified all 14 patients with GD in the analysis set (100% sensitivity) and 27 of 38 patients in the non‐GD group (71% specificity). Patients with LD and HM were most likely to have manifestations overlapping GD. Conclusions: Preliminary validation of the GED‐C PSS discriminated effectively between patients with GD and those with overlapping signs

    Ketones Prevent Oxidative Impairment of Hippocampal Synaptic Integrity through K\u3csub\u3eATP\u3c/sub\u3e Channels

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    Dietary and metabolic therapies are increasingly being considered for a variety of neurological disorders, based in part on growing evidence for the neuroprotective properties of the ketogenic diet (KD) and ketones. Earlier, we demonstrated that ketones afford hippocampal synaptic protection against exogenous oxidative stress, but the mechanisms underlying these actions remain unclear. Recent studies have shown that ketones may modulate neuronal firing through interactions with ATP-sensitive potassium (KATP) channels. Here, we used a combination of electrophysiological, pharmacological, and biochemical assays to determine whether hippocampal synaptic protection by ketones is a consequence of KATP channel activation. Ketones dose-dependently reversed oxidative impairment of hippocampal synaptic integrity, neuronal viability, and bioenergetic capacity, and this action was mirrored by the KATP channel activator diazoxide. Inhibition of KATP channels reversed ketone-evoked hippocampal protection, and genetic ablation of the inwardly rectifying K+ channel subunit Kir6.2, a critical component of KATP channels, partially negated the synaptic protection afforded by ketones. This partial protection was completely reversed by co-application of the KATP blocker, 5-hydoxydecanoate (5HD). We conclude that, under conditions of oxidative injury, ketones induce synaptic protection in part through activation of KATP channels

    Dynamical System Analysis of Cosmologies with Running Cosmological Constant from Quantum Einstein Gravity

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    We discuss a mechanism that induces a time-dependent vacuum energy on cosmological scales. It is based on the instability induced renormalization triggered by the low energy quantum fluctuations in a Universe with a positive cosmological constant. We employ the dynamical systems approach to study the qualitative behavior of Friedmann-Robertson-Walker cosmologies where the cosmological constant is dynamically evolving according with this nonperturbative scaling at low energies. It will be shown that it is possible to realize a "two regimes" dark energy phases, where an unstable early phase of power-law evolution of the scale factor is followed by an accelerated expansion era at late times.Comment: 26 pages, 4 figures. To appear in New Journal of Physic

    Potential Sustainable Cement Free Limecrete Based on GGBS & Hydrated Lime as an Alternative for Standardised Prescribed Concrete Applications

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    A fundamental issue with the active ingredient of concrete, Portland cement, is its energy-intensive manufacturing process, which has led to the cement industry emitting up to 10% of global CO2 levels. To facilitate the reduction in the embodied CO entirely replaced volumetrically with Hydrated Lime (HL) and ground granulated blast furnace slag (GGBS or SL). GGBS was used to replace hydrated lime content in 10% increments up to 100% GGBS. Analysis of compressive and flexural strength and density testing was performed on samples to investigate the mechanical and physical properties at 7, 28 and 91-day curing ages, whilst flexural testing was conducted at 91 days curing age. Four standard mix ratios, 1:1:3, 1:2:3, 1:1:2 and 2:1 was made for comparison. Two curing conditions were tested at 91-day curing age, these being air-cured and water curing. Results have shown the optimum mix ratio to be 1:1:2 for all mixes. The optimum mix being HL 1:1:2 SL80%, water cured exceeding 25MPa. Throughout the different ratios, it can be concluded that the optimum replacement of GGBS lies between 80-90%; it can also be noted that 100% GGBS content sees a significant drop in compressive and flexural strength, indicating the presence of hydrated lime to be a catalyst for strength gain

    A new approach to cosmological perturbations in f(R) models

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    We propose an analytic procedure that allows to determine quantitatively the deviation in the behavior of cosmological perturbations between a given f(R) modified gravity model and a LCDM reference model. Our method allows to study structure formation in these models from the largest scales, of the order of the Hubble horizon, down to scales deeply inside the Hubble radius, without employing the so-called "quasi-static" approximation. Although we restrict our analysis here to linear perturbations, our technique is completely general and can be extended to any perturbative order.Comment: 21 pages, 2 figures; Revised version according to reviewer's suggestions; Typos corrected; Added Reference

    Conservative Therapy is an Effective Option in Patients With Localized Infection After Penile Implant Surgery

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    INTRODUCTION: Traditionally, penile implant (PI) infections have been managed by removal with immediate or delayed replacement. Recently, interest has been focused on conservative therapy (CT) using antibiotic therapy. AIM: To investigate the success rate and predictive factors affecting the outcome of CT in PI infection patients. METHODS: Patients diagnosed with early, localized PI infection were considered candidates for CT. Exclusion criteria included temperature >37.5°C, WBC >13,000/ΌL, and appearance of any sign of sepsis. In patients with purulent drainage, culture swabs were taken and an antibiotic was chosen based on sensitivity results. Oral antibiotics were used until the local infection was completely resolved. Patients were evaluated weekly during this process. RESULTS: Thirty-seven patients were retrospectively reviewed and constituted the study population. Mean age was 58.1 (range 37-85; SD 9.9) years. All were diabetic. Mean BMI was 31.8 (range 24-47; SD 5.0). PI was malleable in 33 cases and inflatable in 4 cases. Culture results (n = 19) included Staphylococcus epidermidis (42 %), pseudomonas (21%), Escherichia coli (21%), and S aureus (16%). Four of 37 patients needed the PI removed due to CT failure and onset of systemic symptoms, at a mean time-point of 75 ± 1.8 days after CT commencement. In men who were cured, mean time to complete healing was 49 (range 29-97; SD 15.8) days. Two of 37 patients (5%) had PI removal because of persistent penile pain despite complete wound healing, at a mean time point of 128 ± 2.5 days after CT commencement. All men managed conservatively resumed sexual intercourse. CONCLUSION: CT of localized PI infection appears to be a viable option for such patients, with the majority of patients retaining their implant and resuming sexual activity

    The metabolomic analysis of five Mentha species: cytotoxicity, anti-Helicobacter assessment, and the development of polymeric micelles for enhancing the anti-Helicobacter activity

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    Mentha species are medicinally used worldwide and remain attractive for research due to the diversity of their phytoconstituents and large therapeutic indices for various ailments. This study used the metabolomics examination of five Mentha species (M. suaveolens, M. sylvestris, M. piperita, M. longifolia, and M. viridis) to justify their cytotoxicity and their anti-Helicobacter effects. The activities of species were correlated with their phytochemical profiles by orthogonal partial least square discriminant analysis (OPLS-DA). Tentatively characterized phytoconstituents using liquid chromatography high-resolution electrospray ionization mass spectrometry (LC-HR-ESI-MS) included 49 compounds: 14 flavonoids, 10 caffeic acid esters, 7 phenolic acids, and other constituents. M. piperita showed the highest cytotoxicity to HepG2 (human hepatoma), MCF-7 (human breast adenocarcinoma), and CACO2 (human colon adenocarcinoma) cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. OPLS-DA and dereplication studies predicted that the cytotoxic activity was related to benzyl glucopyranoside-sulfate, a lignin glycoside. Furthermore, M. viridis was effective in suppressing the growth of Helicobacter pylori at a concentration of 50 mg mL−1. OPLS-DA predicted that this activity was related to a dihydroxytrimethoxyflavone. M. viridis extract was formulated with Pluronic¼ F127 to develop polymeric micelles as a nanocarrier that enhanced the anti-Helicobacter activity of the extract and provided minimum inhibitory concentrations and minimum bactericidal concentrations of 6.5 and 50 mg mL−1, respectively. This activity was also correlated to tentatively identified constituents, including rosmarinic acid, catechins, carvone, and piperitone oxide

    Malleable Penile Implant Is an Effective Therapeutic Option in Men With Peyronie's Disease and Erectile Dysfunction

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    BACKGROUND: The inflatable penile prosthesis (IPP) is typically the preferred implant for Peyronie's disease (PD) and malleable penile prostheses (MPPs) have been discouraged. Aims: To evaluate the effectiveness and patient satisfaction of the MPP vs IPP in patients with PD. METHODS: Men with PD and erectile dysfunction who elected for penile implant surgery constituted the study population. Preoperatively, demographic and comorbidity parameters were recorded. Curvature was measured with a goniometer at maximum rigidity after intracavernosal injection of a vasoactive agent. Postoperatively, overall satisfaction was measured at 3, 6, 12, and 24 months on 5-point Likert scale from 1 (dissatisfied) to 5 (very satisfied). RESULTS: 166 men with a mean age of 59 ± 10 years were analyzed. The mean preoperative curvature in the entire cohort was 65° (range = 30–130°). 94% of patients with MPP had total resolution of their curvature at the end of the operation, whereas 8 patients (6%) had residual curvature (25–40°). In the IPP group 25 of 30 (83.3%) had a straight penis at the end of surgery, whereas 5 of 30 (16.7%) had residual curvature, with the mean magnitude being 33° in the MPP group and 30° in the IPP group. 86% of all patients had diabetes. There were no differences between the 2 implant groups in age, hemoglobin A1c, body mass index, or smoking status. The mean patient satisfaction was 4.42 ± 0.70 (range = 2–5) and there was no difference between the 2 groups. The mean follow-up period was 23.4 months (range = 6–29 months). CONCLUSION: We found that the MPP is as effective as the IPP in curvature correction in patients with PD, with similar patient satisfaction for the 2 groups. Habous M, Farag M, Tealab A, et al. Malleable Penile Implant Is an Effective Therapeutic Option in Men With Peyronie's Disease and Erectile Dysfunction. Sex Med 2018;6:24–29
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