79 research outputs found

    Kinetic analysis of the reduction of zinc and iron oxides from dust and slurry

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    The reduction of zinc and iron oxides from blast-furnace slurry and gas-purification dust at steel furnaces by heating with carbon is studied in physicochemical terms. Kinetic analysis reveals the optimal parameters of furnace reduction. Initial data are obtained for the development of a reduction technology for zinc and iron oxides. © 2013 Allerton Press, Inc

    Scorpion Biodiversity and Interslope Divergence at “Evolution Canyon”, Lower Nahal Oren Microsite, Mt. Carmel, Israel

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    BACKGROUND: Local natural laboratories, designated by us as the "Evolution Canyon" model, are excellent tools to study regional and global ecological dynamics across life. They present abiotic and biotic contrasts locally, permitting the pursuit of observations and experiments across diverse taxa sharing sharp microecological subdivisions. Higher solar radiation received by the "African savannah-like" south-facing slopes (AS) in canyons north of the equator than by the opposite "European maquis-like" north-facing slopes (ES) is associated with higher abiotic stress. Scorpions are a suitable taxon to study interslope biodiversity differences, associated with the differences in abiotic factors (climate, drought), due to their ability to adapt to dry environments. METHODOLOGY/PRINCIPAL FINDINGS: Scorpions were studied by the turning stone method and by UV light methods. The pattern observed in scorpions was contrasted with similar patterns in several other taxa at the same place. As expected, the AS proved to be significantly more speciose regarding scorpions, paralleling the interslope patterns in taxa such as lizards and snakes, butterflies (Rhopalocera), beetles (families Tenebrionidae, Dermestidae, Chrysomelidae), and grasshoppers (Orthoptera). CONCLUSIONS/SIGNIFICANCE: Our results support an earlier conclusion stating that the homogenizing effects of migration and stochasticity are not able to eliminate the interslope intra- and interspecific differences in biodiversity despite an interslope distance of only 100 m at the "EC" valley bottom. In our opinion, the interslope microclimate selection, driven mainly by differences in insolance, could be the primary factor responsible for the observed interslope pattern

    Divergent Effects of Human Cytomegalovirus and Herpes Simplex Virus-1 on Cellular Metabolism

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    Viruses rely on the metabolic network of the host cell to provide energy and macromolecular precursors to fuel viral replication. Here we used mass spectrometry to examine the impact of two related herpesviruses, human cytomegalovirus (HCMV) and herpes simplex virus type-1 (HSV-1), on the metabolism of fibroblast and epithelial host cells. Each virus triggered strong metabolic changes that were conserved across different host cell types. The metabolic effects of the two viruses were, however, largely distinct. HCMV but not HSV-1 increased glycolytic flux. HCMV profoundly increased TCA compound levels and flow of two carbon units required for TCA cycle turning and fatty acid synthesis. HSV-1 increased anapleurotic influx to the TCA cycle through pyruvate carboxylase, feeding pyrimidine biosynthesis. Thus, these two related herpesviruses drive diverse host cells to execute distinct, virus-specific metabolic programs. Current drugs target nucleotide metabolism for treatment of both viruses. Although our results confirm that this is a robust target for HSV-1, therapeutic interventions at other points in metabolism might prove more effective for treatment of HCMV

    Protocol for a randomized, double blind, placebo controlled, crossover trial of Melatonin for treatment of Nocturia in adults with Multiple Sclerosis (MeNiMS)

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    © 2017 The Author(s). Background: Nocturia (the symptom of needing to wake up to pass urine) is common in progressive Multiple Sclerosis (MS) patients. Moderate-to-severe nocturia affects quality of life, can exacerbate fatigue and may affect capacity to carry out daily activities. Melatonin is a natural hormone regulating circadian cycles, released by the pineal gland at night-time, and secretion is impaired in MS. Melatonin levels can be supplemented by administration in tablet form at bedtime. The aim of this study is to evaluate the effect of melatonin on mean number of nocturia episodes per night in MS patients. Secondary outcome measures will assess impact upon quality of life, urinated volumes, lower urinary tract symptoms (LUTS), cognition, sleep quality and sleep disturbance of partners. Methods: A randomized, double blind, placebo controlled, crossover trial consisting of two, six week treatment phases (active drug melatonin 2 mg or placebo), with a 1 month wash-out period in between. The primary outcome (change in nocturia episodes per night) in this two arm, two treatment, two period crossover design, will be objectively measured using frequency volume charts (FVC) at baseline and following both treatment phases. Questionnaires will be used to assess quality of life, sleep quality, safety and urinary tract symptoms. Qualitative interviews of participants and partners will explore issues including quality of life, mechanisms of sleep disturbance and impact of nocturia on partners. Discussion: This study will evaluate whether melatonin reduces the frequency of nocturia episodes in MS patients, and therefore whether 'Circadin' has the potential to reduce LUTS and fatigue, and improve cognition and overall quality of life. Trial registration: (EudraCT reference) 2012-00418321 registered: 25/01/13. ISRCTN Registry: ISRCTN3868786

    Long-term safety and efficacy of Eculizumab in Aquaporin-4 IgG-positive NMOSD

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    Objective During PREVENT (NCT01892345), eculizumab significantly reduced relapse risk versus placebo in patients with aquaporin-4 immunoglobulin G-positive neuromyelitis optica spectrum disorder (AQP4-IgG+ NMOSD). We report an interim analysis of PREVENT's ongoing open-label extension (OLE; NCT02003144) evaluating eculizumab's long-term safety and efficacy. Methods Patients who completed PREVENT could enroll in the OLE to receive eculizumab (maintenance dose = 1,200 mg/2 weeks, after a blinded induction phase). Safety and efficacy data from PREVENT and its OLE (interim data cut, July 31, 2019) were combined for this analysis. Results Across PREVENT and the OLE, 137 patients received eculizumab and were monitored for a median (range) of 133.3 weeks (5.1–276.9 weeks), for a combined total of 362.3 patient-years (PY). Treatment-related adverse event (AE) and serious adverse event (SAE) rates were 183.5 in 100 PY and 8.6 in 100 PY, respectively. Serious infection rates were 10.2 in 100 PY in eculizumab-treated patients versus 15.1 in 100 PY in the PREVENT placebo group. No patient developed a meningococcal infection. At 192 weeks (3.7 years), 94.4% (95% confidence interval [CI], 88.6–97.3) of patients remained adjudicated relapse-free. The adjudicated annualized relapse rate was 0.025 (95% CI = 0.013–0.048) in all eculizumab-treated patients versus 0.350 (95% CI = 0.199–0.616) in the PREVENT placebo group. During the OLE, 37% of patients (44 of 119 patients) stopped or decreased background immunosuppressive therapy use. Interpretation This analysis demonstrates that eculizumab's long-term safety profile in NMOSD is consistent with its established profile across other indications. This analysis also demonstrated the sustained ability of long-term eculizumab treatment to reduce relapse risk in patients with AQP4-IgG+ NMOSD. ANN NEUROL 2021;89:1088–109

    Oxidation process in iron ore materials at low temperatures

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    Using methods of physico-chemical analysis (differentially– thermal and mineralogical) helped to study the oxidation process of magnetite (titanium magnetite) on samples from Olhovsk magnetite and Kachkanar titanium magnetite concentrates at low temperatures (200 – 400 °C). Kinetic curves for the studied materials were obtained at different temperatures; they are typical for topochemical processes. Meanings of specific speeds of oxidation of magnetite various size at different temperatures were calculated and sizes of apparent energy of activation of the process were defined. The influence of partial pressure on kinetics of oxidation in gas phase was studied to expose the limiting point of the process of oxidation of magnetite and titanium magnetite. The order of oxidation reaction on oxygen at definite temperatures and the oxidation degree was calculated using graphical methods. The influence of titanium inclusions in magnetite on kinetics of phase change of magnetite–hematite was examined at the temperature interval of 200 – 400 °C, it happens in mixed operational parameters. Then the process comes to diffusive operational parameters. Kinetic principles and the character of oxidation of the studied materials in nonisothermical conditions were defined at different speeds of heating. These results are of some interest and can be used to optimize the low temperature oxidation regimes of iron ore materials on a conveyor roasting machine. © 2017, National University of Science and Technology MISIS. All rights reserved

    Rib Hump Deformity Correction in Patients with Adolescent Idiopathic Scoliosis: A Comparison of Three Spinal Fusion Systems.

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    The aim of the present study is to control the hypothesis that the rib hump deformity can be adequately corrected when applying vertebral derotation. We retrospectively studied patients treated with full pedicle screw systems (group A), hybrid constructs (group B), and Harrington rod instrumentation (group C). No costoplasties were performed in the patients included in our study. Derotation was applied in groups A and B. The rib hump deformity was assessed on lateral radiographic studies by rib index (RI). Of the 72 patients that were finally included in our study, 30 patients (24 females and 6 males; mean age, 14.5 ± 2.2 years) were treated with a full pedicle screw system, 23 patients (19 females and 4 males; mean age, 13.8 ± 1.9 years) were treated with a hybrid construct, and 19 patients (16 females and 3 males; mean age, 14.3 ± 2 years) received the Harrington rod instrumentation. In all groups RI was significantly corrected after surgery. Before surgery no difference in RI was found among groups; however, after surgery RI was found significantly higher in group C as compared to groups A and B. The between-group analysis revealed that the correction of RI, and thereby the rib hump deformity correction, did not significantly differ among the three patient groups. In conclusion, it cannot be suggested based on the present study that vertebral derotation alone can offer an adequate correction of the rib hump deformity. Further, the development of rib cage deformity and its degree of interdependence with the scoliotic spinal deformity has to be further investigated and assessed, as it seems that it may not necessarily result directly from the primary vertebral deformity
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