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The operation of glass furnaces with oxy-fuel combustion in combination with advanced heat recovery is a compelling low cost solution. Praxair has developed a new heat recovery technology for oxy-fuel fired furnaces in which regenerators are used in a similar way as conventional regenerators, which recover waste heat from the furnace flue gas. The OPTIMELT⁜ Thermo-Chemical Regenerator (TCR) technology uses the stored waste heat to reform a mixture of natural gas and recirculated flue gas to hot syngas, resulting in efficient heat recovery. The natural gas reacts endothermically in the hot checker pack with the water vapor and CO2 in the recycled flue gas, forming H2 and CO as a hot syngas fuel. The OPTIMELT™ TCR system is simple and operated at atmospheric pressure without the need of catalysts or separate steam generation. It reduces fuel consumption of an oxy-fuel fired furnace by about 20% and offers an attractive conversion option for existing air-regenerator furnaces, with more than 30% fuel reduction compared to the air-fuel base case. This technology is currently being demonstrated on a 50 t/d commercial glass furnace at Pavisa. This paper introduces the operating principles of the TCR and highlights some milestones recently achieved at the demonstration site. Initial data from the TCR operation at the host furnace are presented and discussed. [ABSTRACT FROM AUTHOR]

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The V and R light curves for 30 RR Lyrae stars in M15 were used to calculate their physical parameters. The Blazhko effect, previously reported in V12, was not detected. The determined values of the iron content and distance of the cluster are: [Fe/H] = −1.98 ± 0.24 and d = 8.67 ± 0.41 kpc, respectively. The mean values of the physical parameters determined for the RR Lyrae stars place the cluster precisely into the sequences Oosterhoff type – metallicity and metallicity – effective temperature, valid for globular clusters. [ABSTRACT FROM PUBLISHER]

Preseasonal local nasal immunotherapy (LNIT) by means of an extract in macronized powder form has been studied in allergic rhinitis to parietaria. Twenty-four Parietaria-sensitive patients have been studied for 18 weeks in a double-blind controlled trial. Subjects were selected on the basis of a positive skin test, RAST and intranasal challenge to Parietaria antigen. Three eight-patient groups were randomly planned: the first group was given native Parietaria product, the second modified Parietaria product, and the third placebo. During the pollen season no difference was observed in mean weekly symptom score between the three groups, while the mean weekly medication score was significantly lower in the treated groups than the control group. Only the treated groups showed a significant increase in specific nasal threshold to Parietaria after treatment. Adverse reactions to LNIT, limited to the upper respiratory tract, occurred rarely and did not interfere with the dose schedule. This study indicates that LNIT in powder form may be a suitable alternative to the traditional subcutaneous immunotherapy in terms of clinical efficacy and safety. [ABSTRACT FROM AUTHOR]

Objectives: Mechanism of action of biological and synthetic disease-modifying antirheumatic drugs (DMARDs) includes the inhibition of specific proinflammatory cytokines. This study aimed to elucidate the cytokines and chemokines inhibited by different treatments (conventional synthetic DMARD [csDMARD], biological and targeted synthetic DMARD) in rheumatoid arthritis (RA)., Methods: Fifty-nine RA patients with low disease activity or remission included in a cross-sectional study were classified by treatment in groups: abatacept, certolizumab, rituximab (RTX), tocilizumab, tofacitinib (TOF), baricitinib (BAR), and csDMARD. Cytokine and chemokine serum levels were measured by LEGENDplex Human Inflammation panel. Quantitative variables were compared using Student t or Mann-Whitney U test as appropriate, whereas qualitative variables were compared using χ2 or Fisher exact test. p < 0.05 was considered significant., Results: Certolizumab, RTX, tocilizumab, and TOF showed that most cytokine pathways inhibited: tumor necrosis factor α, interferon γ, interleukin 1β (IL-1β), IL-12, IL-18, and IL-23; in addition, csDMARDs showed a similar inhibition patron except for IL-23. Serum level of tumor necrosis factor α pathway was one of the most inhibited being undetectable in RTX, TOF, and BAR groups. Interleukin 6 was shown to be inhibited by abatacept, RTX, and TOF; however, higher levels were observed in 3 patients treated with tocilizumab. Abatacept, certolizumab, RTX, and TOF downregulated IL-10 in this group of patients but remained detectable in almost half of the subjects, with the highest levels in the BAR group. The active pathways that remained the most were CC chemokine ligand 2, IL-8, IL-17, and IL-33., Conclusions: Understanding the cytokine chemokine pathways inhibition could help rheumatologists to prescribe a tailored therapy using the arsenal of DMARDs for individualized RA treatment in an evidence-based decision manner., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background/objectives: Western diet is characterized by a high acid load that could generate various degrees of metabolic acidosis, of which at least the stronger forms are known to contribute to the progression of chronic kidney disease (CKD). The aim of this study was to estimate the potential renal acid load (PRAL) and acid base status in CKD patients attended at the Children's Hospital J.M. de los Ríos in Caracas, Venezuela from April 2015 to February 2016., Subjects/methods: Twenty-seven children with CKD were included. Diet composition was evaluated by a food frequency questionnaire and a 24-h intake reminder. PRAL was calculated by the Remer and Manz method. Laboratory tests included serum creatinine, electrolytes and venous gases., Results: Protein intake was above recommendations in 21 patients (78.6%). Average vegetable and fruit intake was 0.4 and 1.5 servings per day, respectively. Mean PRAL was 16 ± 10.7 mEq/day. PRAL correlated positively with energy (p = 0.005), protein (p = 0.001) and fat intake (p = 0.0001), daily servings of dairy (p = 0.04) meat (p = 0.001) and cereals (0.001) and negatively with vegetable intake (p = 0.04). Serum pH and bicarbonate were 7.3 ± 0.08 and 20.46 ± 4.5 mEq/L, respectively. Twenty-one patients (80.7%) with metabolic acidosis were treated with sodium bicarbonate., Conclusions: Dietary pattern of Venezuelan children with CKD may constitute a risk factor for the progression of the disease by promoting metabolic acidosis via unfavorable dietary acid loads. PRAL should be assessed as a valuable guide for nutritional counseling in children with CKD.

The Cu 2+ , Mn 2+ , and Fe 3+ complexes of a 14 membered macrocycle were synthesized and their antioxidant capacities were evaluated against ABTS and DPPH radicals, with the objective of collecting insights into the biomimetic role of the central metal ions. The macrocycle, abbreviated as H 2 L14, is a derivative of EDTA cyclized with 1,4-diamine, and the moderately flexible macrocyclic frame permits the formation of [ML14·H 2 O] chelates with octahedral coordination geometries common among the metal ions. The metal complexes were characterized by electrospray-ionization mass spectrometry, Fourier transform infrared spectroscopy, and Raman and X-ray photoelectron spectroscopic methods, as well as thermogravimetric analysis; the octahedral coordination geometries with water coordination were optimized by DFT calculations. The antioxidant assays showed that [FeL14·H 2 O] + was able to scavenge synthetic radicals with moderate capacity, whereas the other metal chelates did not show significant activity. The Raman spectrum of DPPH in solution suggests that interaction was operative between the Fe 3+ chelate and the radical so as to cause scavenging capability. The nature of the central metal ions is a controlling factor for antioxidant capacity, as every metal chelate carries the same coordination geometry.

The new rapid scan method, Flyscan mode, implemented on the DiffAbs beamline at Synchrotron SOLEIL, allows fast micro-X-ray fluorescence data acquisition. It paves the way for applications in the biomedical field where a large amount of data is needed to generate meaningful information for the clinician. This study presents a complete set of data acquired after injection of gold-cluster-enriched mesoporous silica nanospheres, used as potential theranostic vectors, into rats. While classical X-ray fluorescence investigations (using step-by-step acquisitions) are based on a limited number of samples (approximately one per day at the DiffAbs beamline), the Flyscan mode has enabled gathering information on the interaction of nanometer-scale vectors in different organs such as liver, spleen and kidney at the micrometer scale, for five rats, in only a single five-day synchrotron shift. Moreover, numerous X-ray absorption near-edge structure spectra, which are beam-time-consuming taking into account the low concentration of these theranostic vectors, were collected.

Background: The lifetime incidence of kidney stones is about two times greater in men compared to women. Extracellular vesicles (EVs) shed from activated cells are present in the urine and may reflect or even mediate renal physiology and/or pathology. This study was designed to standardize methodology to characterize urinary EVs by digital flow cytometry and to identify possible sex differences in EVs in persons with and without their first symptomatic kidney stones., Methods: Twenty-four-hour urine collections were obtained from persons presenting with their first kidney stone episode (n = 50 women, 60 men; age 19-76 years) and sex- and age-matched controls from the general population (n = 24 women, 36 men)., Results: Standardization: Size of EV was variable within all groups. EV positivity was verified with two fluorophores for surface phosphatidylserine and/or using two different protein markers specific for renal-specific cells. The number of phosphatidylserine- and exosome marker-positive EVs did not correlate with urine osmolality and were similar in fresh vs. frozen and between two sequential urine collections from the same individual. Sex differences: Urine from women controls contained greater (P < 0.05) numbers of EVs positive for phosphatidylserine, exosomes, inflammatory factors and adhesion molecules, and cell-specific markers from different segments of the nephron, renal pelvis, and bladder compared to control men. In contrast, urine from women with kidney stones contained significantly (P < 0.05) lower numbers of EVs derived from podocytes, parietal cells, proximal convoluted tubule, thin and thick loop of Henle, distal tubule, collecting duct, renal pelvis, and bladder compared to control women and contained similar quantities of these types of EVs in men with and without kidney stones. There were also no sex differences in EVs positive for cell adhesion (E-cadherin and inter-cellular adhesion molecule-1 [ICAM-1]) molecules., Conclusions: Unlike women who do not have kidney stones, EVs in urine from women with nephrolithiasis are similar to men with and without kidney stones. Thus, EVs may mediate or reflect aspects of kidney stone pathogenesis and perhaps provide clues regarding sex differences in kidney stone incidence rates.