Intermediate Zone Research Articles

Tourmaline as a recorder of the magmatic-hydrothermal evolution in the formation of pegmatite: In-situ elemental and boron isotopic compositions of tourmaline from the Qinghe pegmatite, Chinese Altay orogen

• Tourmalines record the magma-hydrothermal evolution of pegmatite-forming magma . • Extremely low REEs of tourmaline indicate direct melting of metapelite to form pegmatite . • Boron isotopic variation reflects the scale of fluid exsolution during pegmatitic evolution. We conducted elemental and boron isotope studies on tourmalines from a single pegmatite dyke of the Altay orogen to investigate its origin and evolution. The pegmatite dyke is composed of border, intermediate and core zones. The border and intermediate zone tourmalines mostly belong to schorl, while the core zone and magmatic hydrothermal tourmalines to dravite. Most tourmalines follow the (Na + Mg) (Al + X vac ) -1 , FeMg -1 and MnMg -1 exchange vectors. The core zone tourmalines show positively correlated FeO t and MgO, and negatively correlated FeO t and Al 2 O 3 , suggesting a rise of f O2 in this zone. Moreover, they show higher B, Mg, Sr and Eu than other tourmalines due to magmatic evolution. Tourmaline from the Altay pegmatite is characterized by extremely low REE abundances (<3 ppm) when compared with those from granites, suggesting an origin from direct melting of metapelitic rocks. The border and intermediate zone tourmalines have comparable boron isotopic compositions with δ 11 B = −14.0 to −12.2‰, which are similar to the mica schist (−13.2 ‰ to −12.2‰), but slightly heavier than the core zone and magmatic hydrothermal tourmalines (−14.4‰ to −13.3‰). This suggests derivation of the pegmatite from melting of the metapelite without causing boron isotope fractionation, whereas late-stage fluid exsolution caused somewhat boron fractionation. This may be indicative of only small amounts of fluids being released from the barren pegmatite-forming magma. Tourmalines from mineralized pegmatites basically exhibit heavier boron isotope compositions than those from barren pegmatites, due probably to more involvement of evaporate in the source of the former.

Neurotoxicity of phenylalanine on human iPSC-derived cerebral organoids.

Phenylketonuria (PKU) is a common genetic metabolic disorder that causes phenylalanine accumulation in the blood. The most serious symptoms are related to the brain, as intellectual disability, seizure, and microcephaly are commonly found in poorly treated PKU patients and the babies of maternal PKU. However, the mechanism of hyperphenylalaninemia on human neurodevelopment is still unclear. Here we utilized human induced pluripotent stem cell (iPSC)-derived cerebral organoids to investigate the neurotoxicity of hyperphenylalaninemia. Cerebral organoids at days 40 or 100 were treated with different concentrations of phenylalanine for 5 days. After phenylalanine treatments, the cerebral organoids displayed alterations in organoid size, induction of apoptosis, and depletion of neural progenitor cells. However, phenylalanine did not have an impact on neurons and glia, including astrocytes, immature oligodendrocytes, and mature oligodendrocytes. Remarkably, a reduction in the thickness of the cortical rosettes and a decrease in myelination at the intermediate zone were inspected with the elevated phenylalanine concentrations. RNA-seq of phenylalanine-treated organoids revealed that gene sets related to apoptosis, p53 signaling pathway, and TNF signaling pathway via NF-kB were enriched in upregulated genes, while those related to cell cycle and amino acid metabolism were enriched in downregulated genes. In addition, there were several microcephaly disease genes, such as ASPM, LMNB1, and CENPE, ranked at the top of the downregulated genes. These findings indicate that phenylalanine exposure may contribute to microcephaly, abnormal cortical expansion, and myelination lesions in the developing human brain.

The EHA Research Roadmap: Malignant Lymphoid Diseases.

The EHA Research Roadmap: Malignant Lymphoid Diseases.

Ore Mineralization Characteristics in Hydrothermal Alteration at Mangunharjo and Surrounding Areas, Pacitan, Indonesia

The research area is located in Mangunharjo-Grindulu, Pacitan (Indonesia), as part of the Southern Mountain Tertiary Volcanic Arch. Outcrops of quartz veins-riched volcanic rock associated with sulfide minerals are found in this area. The Southern Mountain Oligo-Miocene magmatic arc is known as the potential area that contains precious metal deposits. The study aimed to determine the characteristics of the mineralized zone in this area. The research methods are geological surface mapping, thin-section observation, mineragraphy, and X-Ray Diffraction (XRD). The results show that the constituent lithologies were andesitic lava, breccia, and tuff; co-ignimbrite breccia, dacitic pumice and tuff, and dacitic dike; and pyroxene-rich andesitic volcanic rocks. The geological structure is dominated by oblique normal faults, strike-slip faults, and upward oblique faults associated with shear joints filled with quartz veins. Fieldwork observation, thin-section analyses, and mineragraphic and XRD observations identify three alteration zones in the hydrothermal system: the advanced argillic zone, the intermediate argillic zone, and the chloritized zone. By the mineral’s association, it is interpreted that the advanced argillic zone was formed at a temperature of 220-330oC and pH 3-6 due to dissemination with side rocks located near the hydrothermal flows; the intermediate argillic zone and the chloritized zone were formed at a temperature of 150-300oC and a pH of 5-6 due to chloritized alteration of the hydrothermal fluid carrying the ore. This alteration zone has no economic potential for precious metal minerals so it is better to be developed for education, conservation, and natural laboratories.

Systematic screening for advanced liver fibrosis in patients with coronary artery disease: The CORONASH study.

Although coronary artery disease (CAD) and advanced liver fibrosis (AdLF) are commonly associated in patients with non-alcoholic fatty liver disease (NAFLD), the prevalence of AdLF and the diagnostic performance of non-invasive fibrosis tests (NITs) in CAD patients remains unknown. We aimed to prospectively screen for AdLF in patients with documented CAD using NITs and Fibroscan. High and intermediate zones of NITs were combined to define AdLF. AdLF was suspected whenever APRI ≥ 0.5, Forns index ≥ 4.2, NAFLD fibrosis score (NFS) ≥ -1.455/0.12 for age </≥ 65 yrs), Fib4 (≥ 1.30/2.0 for age </≥ 65 yrs) and eLIFT≥ 8. A presumed AdLF assessed by Fibroscan ≥ 8 kPa was the primary outcome measure. Results were given on the basis of intent-to-diagnose liver stiffness ≥ 8 kPa. Among 189 patients (age 60±7years), 10 (5.3%) had a Fibroscan ≥ 8 kPa, of whom 5 underwent liver biopsy (F3/F4: n = 3; no fibrosis: n = 2). AdLF was suspected in 31% of cases using eLIFT (specificity, Sp 70%), 85% with Forns (Sp 16%), 38% with NFS (Sp 63%), 25% with Fib4 (Sp 74%), and 10% with APRI (Sp 91%). In 149 patients “at-risk” of NAFLD (i.e., elevated ALT or diabetes or hypertriglyceridemia or BMI ≥25 kg/m2), AdLF ranged between 10% (APRI) to 84% (Forns). In this subgroup, the most efficient NITs to predict Fibroscan ≥ 8 kPa were eLIFT (Se 60%, Sp 70%) and NFS (Se 70%, Sp 60%). Finally, in CAD patients with risk factors for NAFLD, NFS or the more user-friendly eLIFT are the most attractive first-line biochemical NITs to discriminate good candidates for Fibroscan.

Trace Elements and Arsenic Speciation of Field and Market Rice Samples in contrasting Agro-climatic Zones in Sri Lanka

Rice is a major source for micro-elements for the Sri Lankan population, across all agro-climatic zones. This current study was conducted to investigate the variation of the metal(loid)s and As speciation in rice grains collected from wet, intermediate and dry zones of Sri Lanka. Field rice (brown rice) and market rice (polished rice) samples were analysed for total elemental profile and As speciation using ICP-MS and IC-ICP-MS, respectively. As, Cd, Co, Fe, Mn, Mo, Rb, Se, Sr and Zn in field grain samples varied across climatic zones. Highest median Cd, Cu, Mo, P, Rb, Se and Zn from wet zone; Co, Fe, Mn from intermediate zone; and As and Sr from dry zone were reported. Field rice (As, 0.3%; Cd, 1%) and market rice (As, 0%; Cd, 3%) samples exceeded maximum permissible levels of As and Cd. However, higher concentrations of both fields, 18% samples for As and 21% samples for Cd, and market, 7% samples for As and 38% samples for Cd, rice exceeded the recommended permissible levels of As and Cd in infant food according to EU regulations. The high per capita consumption and the chronic exposure to As and Cd through rice may cause adverse effects on Sri Lankan children and adults.

Concentration effect of kinetic hydrate inhibitor on hydrate formation and inhibition

Kinetic hydrate inhibitor (KHI) is an eco-friendly and promising technology for hydrate blockage issue in natural gas pipelines, but it remains unclear of how KHI performance would vary at different subcooling and concentration. In this study, the influence of KHI on the kinetics of methane - propane hydrate formation was evaluated with a wide range of subcooling (5–20 ℃) and concentration (100–51000 ppm) conditions, by characterizing the pressure evolution, average hydrate growth rate and hydrate volume fraction. The results put forward a ‘concentration effect’ concept that represented the nonmonotonic relationship between the performance and concentration of KHI, where KHI obtained higher inhibition performance with either relatively low or high concentration, but became almost ineffective at the intermediate concentration zone. Two hypotheses were then proposed to reveal its internal mechanisms, including the ‘weakened adsorption’ hypothesis and the ‘competition’ hypothesis. Results further demonstrated that the above concentration effect became less obvious when the experimental conditions were more contributory for fast hydrate formation, such as the enhanced subcooling and stirring speed. In addition, the universality of concentration effect was preliminarily verified, which was not restricted by the type of KHI or the selected experimental system. To the best of our knowledge, such concentration effect was for the first time systematically investigated and reported in this study, which highlighted the possibility of flexibly selecting the appropriate KHI concentration based on the practical driving force for hydrate formation.

Monensin and its analogues show anti‐glioblastoma activity in an organoid model of cancer

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. Despite numerous clinical trials, the standard of care therapy has remained unchanged for the last decade. One of the main problems contributing to the limited effective treatment options and poor overall survival is the lack of models which can reliably recapitulate tumor heterogeneity. Organoids are 3D self‐organized structures which mimic tumor architecture, microenvironment, and cellular interactions which makes them an improved model for anti‐cancer drug discovery.Monensin (MON) is a polyether ionophore antibiotic characterized by wide range of biological properties including anti‐cancer activity. In order to identify more potent compounds based on the scaffold of MON, we investigated the anti‐GBM activity of 14 novel esters and urethanes of MON. In 3D mini‐ring cell viability assays, we identified seven analogues (IC50 = 91.5 ± 54.4 ‐ 291.7 ± 68.8 nM) more potent towards GBM than the parental MON (IC50 = 612.6 ± 184.4 nM). These analogues induced DNA fragmentation in an organoid model of GBM, suggestive of apoptotic cell death. Furthermore, the most potent analog, compound 1, significantly reduced GBM cell migration, induced PARP cleavage and degradation, increased ɣH2AX signaling and increased expression of the autophagy marker LCII. To investigate the activity of these novel compounds in a tumor microenvironment, we have developed a host:tumor hybrid 3D organoid system. For host tissue, we generated human cerebral organoids (COs) from hiPSCs. The COs displayed multiple neural rosettes with a proliferative zone of neural stem cells (Nestin+), neurons (TUJ1+), primitive ventricular system (SOX2+/Ki67+), intermediate zone (TBR2+) and cortical plate (MAP2+). These findings suggest the level of differentiation and development of our COs as equivalent to early stage human fetal brain. We then co‐cultured RFP‐labeled U87MG cells with fully formed COs. After establishing U87MG tumor formation, hybrid organoids were treated with MON or compound 1. Compound 1 significantly reduced U87MG tumor size after four days of treatment. Our findings highlight the therapeutic potential of MON analogues towards GBM and support further research and clinical development of these compounds.

Orbicular and Nodular Structures in Carbonatite of the Sung Valley Ultramafic-Alkaline-Carbonatite Complex, Shillong Plateau, Meghalaya, NE India: Their Petrogenetic Implications

Abstract Hitherto unknown rare orbicular carbonatites and associated nodular structures occur in the southeastern parts of the Cretaceous Sung valley ultramafic-alkaline-carbonatite complex (SUACC), Shillong plateau, Meghalaya, northeast India. The orbicular structures are formed around fragmented pyroxenite xenoliths and uralitized sodium-richterite nodular patches during emplacement of a calcium-carbonatite plug. The orbicular structures surrounding the xenoliths were formed in at least three stages of chemical disequilibrium represented by three distinct sectors. They are: (i) an innermost shell of sodium-richterite developed around the core of xenoliths. These shells are associated with radial forsterite and/or fine to medium grained granular forsterites. The xenoliths are partially and at times completely metasomatized, due to the metasomatic interaction of the xenolith and the carbonatite melt (antiskarn); (ii) an intermediate zone resembling a “zebra” striped pattern comprising of alternating white calcite-rich and black forsterite-rich bands. These are formed through recrystallization of contaminated carbonatite melt after complex partial resorbtion and assimilation of the pyroxenite xenolith rims; and (iii) an outermost relatively thicker carbonate rich olivine layer formed by late phase intrusion of an ultramafic melt. This is followed by the development of sodium-richterite porphyroblastic grains representing post crystallization sodium metasomatism. Further, proto-orbicules in carbonatite with associated nodular minerals are present adjacent to the orbicular carbonatite suggesting local instability during intrusion at the contact of the pyroxenite xenolith with the calcium-carbonatite host. Apart from reporting the first occurrence of the orbicular carbonatites from the SUACC, petrogenetic implications involving antiskarn due to metasomatic processes induced by carbonatite magmatism is also presented.

Identifying optimal monitoring strategies to predict soil hydraulic characteristics and water contents by inverse modeling

Aim of study: To investigate the monitoring strategies that let us to build effective models able to best estimate water contents, θ and pressure heads, h with the least amount of data. Area of study: Field data was acquired in an experimental plot at Bahía Blanca (Argentina). Material and methods: Field data of θ(t), h(t) for six soil depth were used to optimize the SHP (θr, θs, α, n and Ks) by inverse modeling with HYDRUS 1D. Several scenarios of available data from θ(t) and h(t) were considered: (1) six monitoring depths (6-MD); (2) five monitoring depths (5-MD); (3) four monitoring depths (4-MD). Model accuracy was assessed by comparing the measured and predicted θ and h for each monitoring strategy. Additionally, field measured SHP with independent methods were compared to inversely optimized SHP. Main results: The best fit between predicted and observed θ and h was achieved with the 6-MD strategy. Nevertheless, deterioration of statistics EF and rRMSE in the 5-MD or 4-MD schemes were lower than 10%, depending on the location of the missing data. The observation points that had less importance in parameter prediction corresponded to the intermediate vadose zone and to the deeper layers. The proposed strategies presented a better performance than field measured SHP to reproduce soil water retention curves for each layer of the soil profile. Research highlights: By reducing the number of vertical observations in the profile without harming the final SHP estimation, the resources needed in data monitoring strategies can be greatly enhanced.

Estimating the initial stage in the process of radial-reverse extrusion using a triangular kinematic module

Those parts of solid or hollow blanks whose shape is complex should be produced by means of combined radial-longitudinal extrusion. However, the use of combined extrusion processes with several degrees of flow freedom requires a preliminary assessment of shape formation, which is true, taking into consideration the peculiarities of evolution of strain sites at different stages of deformation. When deforming high blanks, the presence of an intermediate rigid zone can be observed, separating two autonomous strain sites. When constructing an estimation scheme of the initial stage of the process of combined radial-backward extrusion of hollow parts with a flange, the presence of an intermediate rigid zone is taken into consideration. The need to improve the devised estimation scheme is caused by significant deviations in the projected growths of a part from its experimentally derived dimensions. As an alternative to the axial rectangular kinematic module of the lower deformation site, the use of an axial triangular module has been proposed, whose effectiveness is demonstrated in simulating the process of radial-longitudinal extrusion with expansion. The rationality of the proposed replacement was revealed, both for forecasting the forced mode of the deformation process and for the gradual part’s shape formation. This has made it possible to reduce the projected estimates to 10 % in terms of the increase in the size of a part based on a comparative analysis with experimentally derived data. It is recommended to use the devised scheme for modeling the initial stage of the process for relatively high blanks at H0/h1&gt;4…6; the limitation is the degeneration of the intermediate rigid zone. This will contribute to compiling recommendations for expanding the possibilities of using combined radial-backward extrusion of hollow parts with a flange during production

Assessment of Hydrocarbon Pollution in Groundwater Using Electrical Resistivity Method

Hydrocarbon contamination of the groundwater system is a problem facing residents of Ejigbo, Lagos, Southwestern Nigeria. The area hosts the busiest satellite petroleum depots in Nigeria, and residents have attributed pollution of the groundwater system to hydrocarbon spills from possible pipeline leakages. This study aimed to identify and characterize the source and extent of the groundwater system contamination in the study area. The electrical resistivity method was adopted, comprising 2D Electrical resistivity imaging (ERI) and Vertical Electric Sounding (VES) techniques. Data acquired were processed and analyzed to obtain geoelectric sections, longitudinal conductance map and 2D ERI sections for the study area. Three distinct geoelectric zones were delineated, with the intermediate zone identified as the contaminated shallow aquiferous unit. This unit's resistivity values ranged from about 400 - 5000 ohm-m at a depth of 5 - 35 m. On the 2D ERI sections, possible locations of pipeline leakages were identified. On some ERI sections, a linear feature with resistivity value less than 300 ohm-m was observed from the surface down the depth of the entire section, truncating the horizontal flow of the contaminated unit. Generally, the results indicate that the contamination of the shallow aquifer in the area is widespread and mitigation measures should be urgently undertaken.

Design and Analysis of Medium Utility Aircraft Landing Gear

Stress analysis is one of the important works in finding the structural safety and integrity of a structure. In this work, initially, the main landing gear strength calculation based on the ultimate load is carried out analytically. The stress failure exists in the intermediate zone between the support bearing of the wheels and the clamping of the axle to the nose of the aircraft. To determine the causes of the failure, a material analysis was performed. The margin of safety for major components, such as axle, piston, cylinder, and yoke, as well as minor components, such as toggle link, toggle fork, stub fork, and bolts, is determined. Both analytical and FEA results for stresses are compared. It is found out that the factor by which the FEA and analytical results are varying. The margin of safety calculated by analytical work based on ultimate loads gives positive values as expected. The landing gear strength calculations by both analytical and FEA show the maximum stress for different load conditions based on ultimate loads are well within the ultimate strength of that material.

Preparation, microstructure and mechanical properties of steel matrix composites reinforced by a 3D network TiC ceramics

In this study, the porous TiC ceramics were fabricated using the foam replication-reaction sintering method, by adding 20 wt% metal Ti to TiC either through uniform mixing or cladded as a layer on TiC to modify the porous ceramics' strength. Subsequently, the porous TiC ceramics were used as a reinforcement to develop the interpenetrated three-dimensional (3D) network TiC/45 steel composites by employing the melt infiltration method. XRD and SEM analysis confirmed that the Ti-coated porous TiC ceramics possessed a TiC core, an intermediate TiCx zone and a dense outer mixed Ti and TiCx layer. As the composition changed from pure TiC to Ti-coated TiC, the porosity of the porous TiC ceramics decreased from 94.3% to 89.3%, along with an increase in compressive strength from 0.90 MPa to 2.33 MPa. No impurity was observed in any of the 45 steel matrix composites. The composites reinforced with the Ti-coated porous TiC ceramics displayed a continuous 3D network structure reinforcement, while the network structure of Ti mixed porous TiC ceramics reinforcement in the composites was weakly continuous. Both macro and micro double interlocking 3D structures in the composites with Ti-coated network ceramics resulted in excellent hardness, tensile strength and fracture toughness, with the values determined to be 4.11 GPa, 481 MPa and 28.9 MPa m1/2, respectively.

Characterization of Physicochemical and Mechanical Properties of Dumped Municipal Solid Waste in Sri Lanka as Affected by the Climate Zone and Dumping Age

Due to the rapid increase in population and urbanization, municipal solid waste (MSW) generation is increasing. Sri Lanka, in particular, faces serious difficulties in finding new sites for MSW disposal, due to the lack of available space; therefore, the rehabilitation of existing MSW dumping sites and the extension of their services are required to achieve sustainable urban development. To examine suitable rehabilitation techniques, it is essential to identify the physicochemical and mechanical properties of dumped MSW, fully considering climatic conditions, waste composition, and the time since the waste was dumped. In this study, therefore, the physicochemical and mechanical properties of dumped MSW were investigated; the dumped MSW was taken from existing MSW dumping sites in three climate zones in Sri Lanka, namely the Karadiyana site in the wet zone, Udapalatha in the intermediate zone, and Hambantota in the dry zone, and it was taken at different times after being dumped. The results showed that the waste composition and biodegradation of organic materials affected the physicochemical and mechanical properties of the dumped waste. The measured compaction parameters of the “old” sites at Udapalatha and Hambantota were higher compared to the “new” sites. Compaction parameters at the Karadiyana site, on the other hand, were low, at even &gt;20 years since being dumped, probably due to the high amount of scarcely compacted materials. In direct shear tests, both strain hardening and softening of the waste samples were observed, depending on the difference in vertical stress. Based on the Pearson correlations among measured physicochemical and mechanical parameters, it was found that the loss on ignition (LOI) would be a good indicator to quickly assess the mechanical parameters of “new” and “old” waste materials, due to the small sensitivities to waste age and climate conditions in Sri Lanka. In particular, LOI correlated well to measured specific gravity and compaction properties, and the r2 values of correlations exceeded |0.80|.

Chemical Diversity of Teeth and Bone Fragments from a Newly Discovered Upper Muschelkalk Bone Bed from Silesia, Poland

The new exposure of the Upper Muschelkalk clays and dolomites located south of Kalety (Tarnogórski District, Silesia, Poland) provided numerous remains of vertebrates represented by teeth, scales, long bones, and coprolites. Despite the influence of hydrothermal processes leading to dolomitization and Zn-Pb deposit formation, the preservation of fossil remains is good. The taxonomic diversity and accumulation of vertebrate debris in the dolomite are similar to other “bone beds” from the Muschelkalk and the Lower Keuper units. The SEM-EDS, EMP-WDS, and XRD analyses confirm that the examined remains consist of hydroxylapatite containing carbonate ions. Most vertebrate teeth as well as some bone fragments show zoning in the BSE imaging. In tooth cross-sections, three or two zones are preserved: (I) the outermost zone, associated with diagenetic mineralization of enameloid apatite, (II) a intermediate zone (orthodentine), and (III) the most porous internal zone (osteodentine). Decreasing P, Ca, Sr in the composition of the apatite which forms successive zones, is visible from the most external to the central part. Selective diagenetic substitution and adsorption of some elements by apatite crystals can allow recognition of the genetic origin of highly damaged or transported fragments scattered in the sedimentary layers. The chemical behavior of bioapatite, from deposition to digenesis, shows its useful role for identification of the formation process and potential, younger changes (e.g., hydrothermal overprint). The X-ray diffraction data, particularly cell parameters “a” and “c”, can determine the degree of crystallinity and/or diagenesis. Moreover, correlation between some elements/ions (e.g., Sr, Ba, Ca, Mg, F, OH) can be helpful for the identification of the fossil type, especially if the bones are small and incomplete.

Multi-Physical and Electrochemical Coupling Model for the Protonic Ceramic Fuel Cells with H+/e−/O2− Mixed Conducting Cathodes

A protonic ceramic fuel cell (PCFC) has great potential for medium temperature power generation. Its working process, however, is complicated and quite different from the traditional oxygen ionic solid oxide fuel cell (O2−-SOFC) and proton exchange membrane fuel cell (PEMFC). In this paper, a multi-physical model for the PCFC with H+/e−/O2− mixed conducting cathode is established, in which the fuel- and oxidant-diffusing processes; electron-, oxygen ion-, and proton-conducting processes; three electrochemical reactions; and their coupling working details are carefully considered. Taking Ni-BZCY/BZCY/BZCY-LSCF PCFC as an example, the validation of the model is well verified by good agreements with the experiment iop-Vop curves at different temperatures. The result shows that the cathodic electrochemical reactions will be concentrated to a small thickness near the electrolyte because of the greatly decreased ionic conductivity compared with the high electronic conductivity at an intermediate temperature. O2− within the PCFC cathode is only an intermediate transform substance between the electrons and protons. Thus, there is a peak oxygen ion current distribution within the composite cathode of PCFC. The cathodic oxygen reduction half reaction is found to be a key factor to dominate the total PCFC voltage loss at the intermediate temperature zone. The concentration polarization of anode-supported PCFC is small, due to the vapors that are generated in the cathode side instead of anode side.

Vegetative and reproductive phenology of Cinnamomum verum J. Presl grown in intermediate climatic zone of Sri Lanka

The Journal of the National Science Foundation of Sri Lanka publishes the results of research in all aspects of Science and Technology. The journal also has a website at http://www.nsf.gov.lk/. 2021 Impact Factor: 0.682The JNSF provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge.

Reframing Optimal Implantation of the Sapien 3 Transcatheter Heart Valve.

To define the optimal implantation of the Sapien 3 (Edwards Lifesciences) transcatheter heart valve (THV), this study systematically analyzed the predeployment fluoroscopic THV position and correlated this to clinical outcomes. This was an observational study of 279 patients treated with the Sapien 3 THV. Fluoroscopic imaging was used to categorize patients into low (n = 147), intermediate (n = 86), and high (n = 46) implantation zones. These zones were based on the relationship of the balloon marker and radiolucent line of the valve frame (line of lucency) to the annular plane at deployment. The primary outcome was the rate of permanent pacemaker implantation (PPI) at 30 days. The secondary outcomes were the rates of new left bundle-branch block (LBBB) in-hospital and all-cause mortality at 1 year. In the high, intermediate, and low groups, 30-day PPI rates were 4.3%, 8.1%, and 8.8% (P=.62); in-hospital LBBB rates were 10.9%, 26.7%, and 32.0% (P=.02); and all-cause mortality rates at 1 year were 3.1%, 7.3%, and 12.5% (P=.14), respectively. No differences were observed with respect to procedural success/complications or THV performance between the groups. This study demonstrates fewer conduction abnormalities for Sapien 3 valves positioned within a higher zone defined fluoroscopically by the line of lucency and balloon marker.

Modeling of blast furnace melt processes when changing the program of charging the burden

The publication presents the results of a predictive assessment of the modeling of processes and final indicators of blast-furnace smelting with a change in the charge loading program for a blast furnace with a volume of 1719 m3, followed by comparison with the actual results obtained. Modeling was carried out using a mathematical model of blast-furnace smelting, which, in contrast to obtaining balance indicators, makes it possible to obtain knowledge about the mechanism of the processes due to which changes occur, including the uneven distribution of charge materials on the top of the blast furnace. The change in the distribution of the ore load was expressed in a decrease by 15-20% of the ore load in the radial ring zones 1-3, where their values in the first period did not exceed 1.0 and an increase in the ore load in the most loaded radial ring zones 5-10 by 2-10%. This led to the displacement of gas isotherms in the central and intermediate radial annular zones upwards, and only in the peripheral zone downwards. At the same time, the temperature difference between the gas and the charge also increased, especially in the upper part, and the softening and melting zone shifted upwards in most of the radial annular zones, except for the peripheral one - 10. The resulting value of heat transfer in the charge column is the gas temperature at the outlet of the charge column. The nature of its change along the radius of the blast furnace is the same for the values calculated by the model and those measured in the blast furnace and indicates an increase in the temperature of the flue gases when using the program for loading the second period. Similar curves for the degree of use of CO gas, obtained by calculation according to the model. From the obtained results, it follows that in lightly loaded radial annular zones, heating to a given temperature occurs at higher horizons, and in heavily loaded ones, at the lowest-high-temperature horizons, requiring heat transfer intensification and measures to improve energy utilization. Without additional measures, a decrease in the use of heat and a corresponding increase in the temperature of the exhaust gases with a reduction in the degree of use of the reducing ability of gases is inevitable, which is obtained as a result of calculations.