Evaluasi Ketidakpastian Pengukuran Multi-Unsur Dalam Mineral Zirkon Dengan Metode Analisis Aktivasi Neutron

Evaluasi analisis multi-unsur yang disertai perhitungan ketidakpastian unsur pada mineral zirkon yang berasal dari Sampit, Kalimantan Tengah dan Pulau Bangka telah dilakukan dengan metode Analisis Aktivasi Neutron (AAN). Tujuan penelitian ini adalah menentukan komposisi dan nilai ketidakpastian multi-unsur dalam mineral zirkon untuk memenuhi persyaratan ISO/IEC guide 17025-2008 yang telah diterapkan pada laboratorium AAN. Analisis menggunakan spektrometri gamma dengan detektor HPGe menghasilkan 21 unsur terdeteksi yang dibagi menjadi tiga kelompok (mayor, minor, dan kelumit). Evaluasi ketidakpastian pengukuran perlu dilakukan untuk meningkatkan kualitas dan tingkat kepercayaan hasil analisis. Hasil pengujian tidak akan bermakna tanpa disertai perhitungan ketidakpastian. Oleh karena itu, dilakukan evaluasi nilai perhitungan ketidakpastian pada hasil analisis semua unsur yang terkandung dalam mineral zirkon. Hasil analisis kuantitatif tertinggi adalah zirkonium (Zr) dengan konsentrasi 38,986% dan mempunyai nilai ketidakpastian 0,33% sehingga nilai konsentrasi nyata adalah 38,986±0,33%, dalam oksida (ZrO2) mempunyai konsentrasi 52,661±0,45%. Unsur stibium (Sb) adalah unsur yang terdeteksi paling rendah dengan nilai konsentrasi dan ketidakpastian adalah 7±0,3 μg/g sedangkan dalam oksida (Sb2O3) mempunyai konsentrasi 17±0,9 μg/g. Komposisi oksida dan bahan kimia dalam mineral pasir zirkon yang lebih signifikan berasal dari Sampit dengan kandungan ZrO2+HfO2 (53-55%), F2O3 (5-6%), TiO2 (13-14%), Al2O3 (1,5-2%) dan SiO2. Unsur Si (SiO2) tidak dapat ditentukan dengan metode AAN sebab tampang lintang Si sangat kecil. The evaluation of multi-elements analysis has been carried out with calculation of element uncertainy in the zircon mineral from Sampit (Central Kalimantan) dan Bangka has been evaluated by the Neutron Activation Analysis (NAA) method. The purpose of this research is determination of composition and value of multi-elements uncertainty in the mineral of zircon to fulfil the requirements of ISO/IEC guide 17025-2008 that applied at NAA laboratory. The result of analysis using gamma spectrometry with a HPGe detector showed of 21 detected elements, divided into three groups (major, minor, and trace). Evaluation of uncertainty estimation should be done to increase quality and confidence rate of analysis results. The result of testing are not mean without calculation of uncertainty. Therefore, it was assessed the uncertainty measurement of all elements analysis in zircon mineral. The results of quantitative analysis is Zr with the highest concentration value of 38.986% and value of uncertainty is 0.331% so that value of real concentration is 38.986 ± 0.331%. In the form of oxide (ZrO2) has concentration of 52.661±0.45%. Sb element is the lowest element detected with value of concentration and uncertainty is 7±0,3 µg/g. In the form of oxide (Sb2O3) has concentration is 17±0.9 µg/g. The oxide composition and the must important of chemicals in the zircon sand mineral more significant from Sampit which quantitative composition areZrO2+HfO2 (53-55%), F2O3 (5-6%), TiO2 (13-14%), Al2O3 (1.5-2%) and SiO2. Elements ofSi(SiO2) can not be determinedbyNAAmethodbecauseSi cross-sections is verysmall

Analysis of Going Concern Audit Opinion Receiving Trends at Property Companies in Indonesia

Responsibilities of auditors currently do not only focus on assessing the fairness of financial statements and detecting fraud, but also assess the company's ability to maintain its survival. “This is due to the demands of the shareholders to the auditor to provide early warning about the prospects of a company as consideration before deciding on an investment decision”. This study aims to determine the effect of financial distress, debt default, and company size on going concern audit opinion. This research uses quantitative research methods. This research data uses secondary data through documentation and literature studies. “The population in this study are property companies listed on the Indonesia Stock Exchange in 2016 – 2018. “The sample in this study amounted to 171 observational data from 57 companies selected using the purposive sampling method”The analysis used in this study is logistic regression analysis at the 5% significance level. “The results of hypothesis testing show that financial distress and company size do not affect going concern audit opinion, while debt default has a significant positive effect on going concern audit opinion”. Keywords: Going concern Audit Opinion, Financial distress, Debt default, Firm Size DOI: 10.7176/RJFA/11-18-03 Publication date:September 30th 202

Mechanical properties of particleboard using acacia mangium wood particles binded with seaweed-based adhesives

The purpose of this study was to evaluate the mechanical properties of particleboards made from Acacia mangium wood particles binded with three different types of seaweed-based adhesive. Red seaweed (RS), brown seaweed (BS) and green seaweed (GS) were used as the seaweed-based adhesives., while particleboard using urea formaldehyde (UF) adhesive was produced as control. Adhesives and wood particles were mixed and then undergone mat-forming, pre-pressing, hot-pressing and conditioning process. The test pieces for bending test (Modulus of Elasticity, MOE; Modulus of Rupture, MOR), and internal bonding strength (IB) were cut into size according to JIS A 5908: 2003. From mechanical properties results attained, for internal bonding strength test, all boards using RS, BS and GS adhesives were found to be significantly different at p≤0.05. Apart from that, RS adhesive showed highest MOE and MOR at 529.4259 N/mm2 and 1.7900 N/mm2, respectively. As a conclusion, the mechanical properties of particleboard using RS, BS, and GS adhesives showed RS stands out as the better adhesive among them which have significant effects on its strength

Prenex Separation Logic with One Selector Field

International audienceWe show that infinite satisfiability can be reduced to finite satisfiabil-ity for all prenex formulas of Separation Logic with k ≥ 1 selector fields (SL k). This fact entails the decidability of the finite and infinite satisfiability problems for the class of prenex formulas of SL 1 , by reduction to the first-order theory of a single unary function symbol and an arbitrary number of unary predicate symbols. We also prove that the complexity of this fragment is not elementary recursive, by reduction from the first-order theory of one unary function symbol. Finally, we prove that the Bernays-Schönfinkel-Ramsey fragment of prenex SL 1 formulas with quantifier prefix in the language ∃ * ∀ * is PSPACE-complete

Thrombin generation in human coronary arteries after percutaneous transluminal balloon angioplasty

AbstractObjectives. The aim of this study was to investigate the relation between coronary atherosclerotic plaque injury and activation of the coagulation cascade.Background. Thrombus formation after atherosclerotic plaque disruption has been implicated in the pathogenesis of atherosclerosis, unstable angina and myocardial infarction.Methods. Biochemical markers of thrombin generation (prothrombin fragment F1+2) and thrombin activity (fibrinopeptide A) were measured in coronary blood before, during and immediately after percutaneous transluminal coronary angioplasty. After demonstrating that blood withdrawal through an angioplasty catheter does not artifactually elevate the plasma levels of these markers in patients after heparinization, coronary artery samples ware collected proximal and distal to the lesion before and distal to the lesion after baltoon inflation in 26 patients.Results. Plasma levels of F1+2measured proximal to the lesion before angioplasty (median 0.47 nmol/liter, 95% confidence interval [CI] 0.40 to 0.50) were significantly elevated after angioplasty (median 0.55 nmol/liter, 95% CI 0.46 to 0.72, p = 0.001). In contrast, plasma fibrinopeptide A levels measured proximal to the lesion before angioplasty (median 2.0 ng/ml, 95% CI 1.3 to 22) were similar to those measured after angioplasty (median 1.8 ng/ml, 95% CI 1.3 to 3.0, p = NS). After we defined a normal range of interassay variability on the basis of values obtained from samples drawn proximal and distal to the lesion before angioplasty, seven patients (27%) had a significant increase in F1+2plasma levels. A significant increase in plasma fibrinopeptide A occurred in five of these seven patients. Lesions with dissection, filling defects or haziness on postangioplasty angiography were associated with more thrombin generation than lesions without these features.Conclusions. Markers of thrombio generation and activity can be collected safely and assayed accurately in heparinized blood withdrawn through aa angioplasty catheter. Balloon dilation of coronary stenoses increases thrombin generation and activity within the coronary artery in a substantial subgroup of patients undergoing angioplasty

Chronic Embolic Pulmonary Hypertension Caused by Pulmonary Embolism and Vascular Endothelial Growth Factor Inhibition

Our understanding of the pathophysiological basis of chronic thromboembolic pulmonary hypertension (CTEPH) will be accelerated by an animal model that replicates the phenotype of human CTEPH. Sprague-Dawley rats were administered a combination of a single dose each of plastic microspheres and vascular endothelial growth factor receptor antagonist in polystyrene microspheres (PE) + tyrosine kinase inhibitor SU5416 (SU) group. Shams received volume-matched saline; PE and SU groups received only microspheres or SU5416, respectively. PE + SU rats exhibited sustained pulmonary hypertension (62 ± 13 and 53 ± 14 mmHg at 3 and 6 weeks, respectively) with reduction of the ventriculoarterial coupling in vivo coincident with a large decrement in peak rate of oxygen consumption during aerobic exercise, respectively. PE + SU produced right ventricular hypokinesis, dilation, and hypertrophy observed on echocardiography, and 40% reduction in right ventricular contractile function in isolated perfused hearts. High-resolution computed tomographic pulmonary angiography and Ki-67 immunohistochemistry revealed abundant lung neovascularization and cellular proliferation in PE that was distinctly absent in the PE + SU group. We present a novel rodent model to reproduce much of the known phenotype of CTEPH, including the pivotal pathophysiological role of impaired vascular endothelial growth factor-dependent vascular remodeling. This model may reveal a better pathophysiological understanding of how PE transitions to CTEPH in human treatments

Association of Altered Collagen Content and Lysyl Oxidase Expression in Degenerative Mitral Valve Disease

Background—Collagen cross-linking is mediated by lysyl oxidase (LOX) enzyme in the extracellular matrix (ECM) of mitral valve leaflets. Alterations in collagen content and LOX protein expression in the ECM of degenerative mitral valve may enhance leaflet expansion and disease severity. Methods—Twenty posterior degenerative mitral valve leaflets from patients with severe mitral regurgitation were obtained at surgery. Five normal posterior mitral valve leaflets procured during autopsy served as controls. Valvular interstitial cells (VICs) density was quantified by immunohistochemistry, collagen types I and III by picro-sirius red staining and immunohistochemistry, and proteoglycans by alcian blue staining. Protein expression of LOX and its mediator TGFβ1 were quantified by immunofluorescence and gene expression by PCR. Results—VICs density was increased, structural type I collagen density was reduced, while reparative type III collagen and proteoglycan densities were increased (p \u3c 0.0001) with an increase in spongiosa layer thickness in myxomatous valves. These changes were associated with a reduction in LOX (p \u3c 0.0001) and increase in TGFβ1 protein expression (p \u3c 0.0001). However, no significant change was seen in gene expression. Linear regression analysis identified a correlation between type I collagen density and LOX grade (R2 = 0.855; p \u3c 0.0001). Conclusions—Reduced type I collagen density with a simultaneous increase in type III collagen and proteoglycan densities possibly contributes to spongiosa layer expansion resulting in incompetent mitral valve leaflets. Observed changes in type I and III collagen densities in DMVD may be secondary to alterations in LOX protein expression, contributing to disorganization of ECM and disease severity

Analysis of energy and exergy for the flat plate solar air collector with longitudinal fins embedded in paraffin wax located in baghdad center

Latent heat of the fusion for the Phase changeable materials (PCM) can be utilized as heat energy store, and this energy can be employed in different applications. In present experimental work, effect of using the embedded longitudinal fins within the paraffin wax, on the energy and exergy performance for the solar air collector was investigated under the Baghdad governorate climate. Compared with the collector without paraffin wax, the results indicated that using of paraffin wax as a thermal storage material reduces the losses of energy and exergy of the collector, high levels of heat reduction by using PCM/Fins were about 33 and 40% respectively at the peak heat charging time (12:30 PM), while the decreasing in energy and exergy losses of the collector with PCM only was about 24 and 30% respectively at the same time of charging (12:30 PM). Due to the going of sum heat to store in the paraffin wax at the charging heat time, the energy along with exergy heat gains, while efficiencies were decreased with and without fins, this decreasing in the heat was the most by using PCM/Fins and it was around 30 and 44%, respectively for energy and exergy efficiencies, while it was about 20 and 31% by using PCM only at the same time of testing. The benefit of using embedded longitudinal fins in PCM is to enhance the thermal storage efficiency by about 6% compared with the solar collector that uses PCM only