Aktivno lužnati kompoziti dobiveni od troske željezne i čelične industrije

Slag as a secondary raw material from metallurgy is most often heaped in slag disposal areas without any profit. This paper deals with alkali activated slag from iron and steel production which can be used in the building industry. Products of alkali slag activation fulfill the role of inorganic binders.Kao sekundarna sirovina, troska od metalurškog procesa najčešće se odlaže na deponije bez ikakve financijske dobiti. Ovaj rad se bavi lužnato aktiviranom troskom iz proizvodnje željeza i čelika, koja kao anorgansko vezivo može biti korištena u građevinskoj industriji

Analysis of coupled heat and moisture transfer in masonry structures

Evaluation of effective or macroscopic coefficients of thermal conductivity under coupled heat and moisture transfer is presented. The paper first gives a detailed summary on the solution of a simple steady state heat conduction problem with an emphasis on various types of boundary conditions applied to the representative volume element -- a periodic unit cell. Since the results essentially suggest no superiority of any type of boundary conditions, the paper proceeds with the coupled nonlinear heat and moisture problem subjecting the selected representative volume element to the prescribed macroscopically uniform heat flux. This allows for a direct use of the academic or commercially available codes. Here, the presented results are derived with the help of the SIFEL (SIimple Finite Elements) system.Comment: 23 pages, 11 figure

Usporedba kakvoće strojno otkoštenog mesa peradi upotrebom različitih postupaka separacije

Selected parameters of quality (hydroxyproline, calcium, bone particles content, and histological determination of bone particles) of mechanically deboned poultry meat (MDPM - „firmseparation“ and soft separation „Baadermeat“) were compared. Comparison of results with composition (except bone particles) of fresh poultry meat (breast and thigh muscles) was performed. Hydroxyproline content was significantly different and the mean value of hydroxyproline content was in mechanically deboned meat more than two-fold higher in comparison with Baader meat (333.17 mg.100g-1, 152.90 mg.100g-1 respectively). Similar results were achieved in calcium content (1.94g.kg-1, 1.05 g.kg-1 respectively). The mean content of bone particles was 0.27 % (MDPM) and 0.034 % (Baader). Finally, histological determination of bone particles in MDPM and Baader meat was carried out.U radu su uspoređeni odabrani parametri kakvoće (hidroksiprolin, kalcij, sadržaj čestica kostiju i histološko određivanje čestica kostiju) strojno otkošteog mesa peradi (engl. mechanically deboned poultry meat; MDPM -„čvrsta separacija“ i „meka separacija“ „Baader meso“). Rezultati su uspoređeni sa sastavom (izuzev koštanih čestica) svje žeg pilećeg mesa (mišići prsiju i bataka). Sadržaj hidroksi prolina pokazivao je značajne razlike, a srednja vrijednost sadržaja hidroksiprolina u strojno otkoštenom mesu bila je dvostruko veća u odnosu na „Baader meso“ (333,17 mg.100g-1, odnosno 152,90 mg.100g-1). Analiza sadržaja kalcija dala je slične rezultate (1,94g.kg-1, odnosno 1,05 g.kg-1). Srednji sadržaj čestica kostiju iznosio je 0,27 % (MDPM) i 0,034 % („Baader“). Provedeno je histološko određivanje čestica kostiju u MDPM i „Baader“ mesu

Usporedba kakvoće strojno otkoštenog mesa peradi upotrebom različitih postupaka separacije

Selected parameters of quality (hydroxyproline, calcium, bone particles content, and histological determination of bone particles) of mechanically deboned poultry meat (MDPM - „firmseparation“ and soft separation „Baadermeat“) were compared. Comparison of results with composition (except bone particles) of fresh poultry meat (breast and thigh muscles) was performed. Hydroxyproline content was significantly different and the mean value of hydroxyproline content was in mechanically deboned meat more than two-fold higher in comparison with Baader meat (333.17 mg.100g-1, 152.90 mg.100g-1 respectively). Similar results were achieved in calcium content (1.94g.kg-1, 1.05 g.kg-1 respectively). The mean content of bone particles was 0.27 % (MDPM) and 0.034 % (Baader). Finally, histological determination of bone particles in MDPM and Baader meat was carried out.U radu su uspoređeni odabrani parametri kakvoće (hidroksiprolin, kalcij, sadržaj čestica kostiju i histološko određivanje čestica kostiju) strojno otkošteog mesa peradi (engl. mechanically deboned poultry meat; MDPM -„čvrsta separacija“ i „meka separacija“ „Baader meso“). Rezultati su uspoređeni sa sastavom (izuzev koštanih čestica) svje žeg pilećeg mesa (mišići prsiju i bataka). Sadržaj hidroksi prolina pokazivao je značajne razlike, a srednja vrijednost sadržaja hidroksiprolina u strojno otkoštenom mesu bila je dvostruko veća u odnosu na „Baader meso“ (333,17 mg.100g-1, odnosno 152,90 mg.100g-1). Analiza sadržaja kalcija dala je slične rezultate (1,94g.kg-1, odnosno 1,05 g.kg-1). Srednji sadržaj čestica kostiju iznosio je 0,27 % (MDPM) i 0,034 % („Baader“). Provedeno je histološko određivanje čestica kostiju u MDPM i „Baader“ mesu

β-Adrenergic Receptor Stimulation and Alternans in the Border Zone of a Healed Infarct: An ex vivo Study and Computational Investigation of Arrhythmogenesis

Background: Following myocardial infarction (MI), the myocardium is prone to calcium-driven alternans, which typically precedes ventricular tachycardia and fibrillation. MI is also associated with remodeling of the sympathetic innervation in the infarct border zone, although how this influences arrhythmogenesis is controversial. We hypothesize that the border zone is most vulnerable to alternans, that β-adrenergic receptor stimulation can suppresses this, and investigate the consequences in terms of arrhythmogenic mechanisms.Methods and Results: Anterior MI was induced in Sprague-Dawley rats (n = 8) and allowed to heal over 2 months. This resulted in scar formation, significant (p < 0.05) dilation of the left ventricle, and reduction in ejection fraction compared to sham operated rats (n = 4) on 7 T cardiac magnetic resonance imaging. Dual voltage/calcium optical mapping of post-MI Langendorff perfused hearts (using RH-237 and Rhod2) demonstrated that the border zone was significantly more prone to alternans than the surrounding myocardium at longer cycle lengths, predisposing to spatially heterogeneous alternans. β-Adrenergic receptor stimulation with norepinephrine (1 μmol/L) attenuated alternans by 60 [52–65]% [interquartile range] and this was reversed with metoprolol (10 μmol/L, p = 0.008). These results could be reproduced by computer modeling of the border zone based on our knowledge of β-adrenergic receptor signaling pathways and their influence on intracellular calcium handling and ion channels. Simulations also demonstrated that β-adrenergic receptor stimulation in this specific region reduced the formation of conduction block and the probability of premature ventricular activation propagation.Conclusion: While high levels of overall cardiac sympathetic drive are a negative prognostic indicator of mortality following MI and during heart failure, β-adrenergic receptor stimulation in the infarct border zone reduced spatially heterogeneous alternans, and prevented conduction block and propagation of extrasystoles. This may help explain recent clinical imaging studies using meta-iodobenzylguanidine (MIBG) and 11C-meta-hydroxyephedrine positron emission tomography (PET) which demonstrate that border zone denervation is strongly associated with a high risk of future arrhythmia

NT‐proBNP predicts mortality in adults with transposition of the great arteries late after Mustard or Senning correction

Objective The patients after Mustard and Senning corrections of transposition of the great arteries (TGA) are at an increased risk of unexpected death. The aim of this study was to identify markers allowing risk stratification of patients after atrial switch correction of TGA to provide them with optimum care. Methods and Results In this study, 87 patients were retrospectively evaluated after atrial switch correction of TGA followed‐up between 2005 and 2015. The mortality during the follow‐up was 9% (8 cardiac deaths). Markers significantly predictive of death using univariable Cox proportional hazard ratio survival analysis were: N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP), ejection fraction and end‐diastolic dimension of the systemic right ventricle, mitral E, e′, and s′. Surprisingly, the Doppler parameters of mitral valve in subpulmonary ventricle were more important for prognosis than those of systemic tricuspid valve. In multivariable analysis, the only independent predictors of mortality were NT‐proBNP (P = .00048; AUC 0.97) and the velocity of early diastolic filling (mitral E) in subpulmonary ventricle (P = .01815; AUC 0.81). According to Kaplan–Meier survival analysis, patients with NT‐proBNP > 1000 pg/ml are at high risk of death. Patients with mitral E ≺ 68 cm/s are also at an increased risk of death. Conclusions NT‐proBNP is the most reliable prognostic mortality factor and should be measured regularly in TGA patients after Mustard or Senning correction. Diastolic filling velocity of the subpulmonary left ventricle (mitral E) may be more important for prognosis than systolic function of the systemic right ventricle

NT‐proBNP predicts mortality in adults with transposition of the great arteries late after Mustard or Senning correction

Objective The patients after Mustard and Senning corrections of transposition of the great arteries (TGA) are at an increased risk of unexpected death. The aim of this study was to identify markers allowing risk stratification of patients after atrial switch correction of TGA to provide them with optimum care. Methods and Results In this study, 87 patients were retrospectively evaluated after atrial switch correction of TGA followed‐up between 2005 and 2015. The mortality during the follow‐up was 9% (8 cardiac deaths). Markers significantly predictive of death using univariable Cox proportional hazard ratio survival analysis were: N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP), ejection fraction and end‐diastolic dimension of the systemic right ventricle, mitral E, e′, and s′. Surprisingly, the Doppler parameters of mitral valve in subpulmonary ventricle were more important for prognosis than those of systemic tricuspid valve. In multivariable analysis, the only independent predictors of mortality were NT‐proBNP (P = .00048; AUC 0.97) and the velocity of early diastolic filling (mitral E) in subpulmonary ventricle (P = .01815; AUC 0.81). According to Kaplan–Meier survival analysis, patients with NT‐proBNP > 1000 pg/ml are at high risk of death. Patients with mitral E ≺ 68 cm/s are also at an increased risk of death. Conclusions NT‐proBNP is the most reliable prognostic mortality factor and should be measured regularly in TGA patients after Mustard or Senning correction. Diastolic filling velocity of the subpulmonary left ventricle (mitral E) may be more important for prognosis than systolic function of the systemic right ventricle

Alkali-activated composites based on slags from iron and steel metallurgy

Slag as a secondary raw material from metallurgy is most often heaped in slag disposal areas without any profit. This paper deals with alkali activated slag from iron and steel production which can be used in the building industry. Products of alkali slag activation fulfill the role of inorganic binders