bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Bonding Temperature and Interlayer(s) on Microstructure Evolution, Hardness, and Shear Properties of Diffusion Bonded Ti-6Al-4V Alloys
Authors: Raj Manil , N. V. Prasad M. J. , Narasimhan K. 
Published: June 2021

Abstract
The workhorse Ti-6Al-4V alloy has numerous applications under extreme conditions, and there is a necessity to produce metallic joints with the alloy for fabrication of some industrial components. In the present study, the solid-state diffusion bonding (DB) process was used to produce similar metal joints between Ti-6Al-4V alloy sheets with and without copper and nickel interlayers. The effect of the bonding temperature as well as the influence of interlayers on the joint interface microstructure and, subsequently, on the mechanical performance of the bonded joints were investigated. The DB was performed at three different bonding temperatures of 1,023, 1,123, and 1,223 K under high-vacuum conditions using a thermomechanical deformation simulator. The microstructure across interface of the joint was examined using optical and scanning electron microscopes. The joint strength was evaluated using both the nanoindentation technique and the shear test. The findings show the formation of intermetallic phases between titanium and interlayer(s) elements across the interface up to the bonding temperature of 1,123 K. Further increase in the bonding temperature led to a complete diffusion of the interlayers into the base metals, thereby forming the Widmanstätten microstructure across the interface. In the case of direct DB, there was a gradual closure of voids along with a homogenized joint interface with an increase in the bonding temperature. The variation of hardness across the bonding interface and the shear properties were found to be consistent with the resultant microstructural features evolved with the bonding temperature and type of interlayer(s).
Word Portfolio Optimization in the Environment of Zero Interest Rate
Authors: Demcenko Darja 
Published: June 2021

This paper provides a deep analysis of ten globally diversified portfolios, composed of different financial instruments: bonds, shares, ETF’s, commodities, indexes, currencies, constructed applying various optimization techniques. Statistical moments, such as mean, standard deviation, kurtosis and skewness of portfolios are compared and discussed. Moreover, performance of the portfolios within the time horizon of one year estimating Sharpe ratio, Treynor ratio, Sortino ratio is presented. Furthermore, a risk analysis of created portfolios is evaluated in terms of historical VaR and CVaR applying confidence interval 95%. The main results of this paper reveal that the portfolio, which is optimized to minimize VaR produces high expected shortfall. Secondly, the Risk Parity portfolio, despite reducing volatility, has delivered the highest kurtosis of the return, which may indicate the possible tail loss. Furthermore, the maximum Sharpe ratio portfolio has delivered extremely high kurtosis in comparison with the kurtosis of the other portfolios. Finally, it is observed that for the Naïve diversification portfolio it has been typical to have the highest downside deviation.
Serological survey of Coxiella burnetii infections in dairy cattle, sheep, goats and zoo animals in Hungary – Short communication
Authors: Dobos Attila , Fodor István , Kiss Gerda , Gyuranecz Miklós 
Published: June 2021

AbstractQ fever is a disease of high zoonotic potential, but interest in its causative agent is rather low although it causes some public health problems in Hungary. The prevalence of Q fever is highly variable by country. The main reservoirs of the disease are the same domestic ruminant species everywhere, but the epidemiological profile depends on the features of the specific reservoir. The aim of this large-scale study was to demonstrate the importance of Q fever in different species as a possible source for human infection in most regions of Hungary. A total of 851 serum samples from 44 dairy farms, 16 sheep flocks, 4 goat farms and 3 zoos located in different parts of Hungary were tested. The presence of antibodies to Coxiella burnetii was surveyed in dairy cattle (n = 547), goats (n = 71), sheep (n = 200) and zoo animals (n = 33). The animal species tested in Hungary showed different seroprevalence values of C. burnetii infection. Seropositivity by the enzyme-linked immunosorbent assay was found in 258 out of 547 (47.2%) cows and in 69 out of 271 (25.5%) small ruminants, among them in 47 out of 200 (23.5%) sheep and in 22 out of 71 (31.0%) goats. Antibodies to C. burnetii were not detected in zoo animals. Seropositivity was demonstrated in 44 out of 44 (100%) dairy cattle farms, with at least one serum sample found to be positive on each farm. The seropositivity rate of small ruminant farms was 55.0% (11 positive out of 20 tested), with 9 out of 16 (56.3%) sheep flocks and 2 out of 4 (50.0%) goat herds showing seropositivity.
BIOACTIVE SAPONINS FROM PANAX BIPINNATIFIDUS SEEM. GROWING IN VIETNAM
Authors: Nguyen Hoang Anh Thi , Nguyen Tung Huu , Pham Hieu Trung , Pham Duong Quang , Le Dang Quang , Vu Hoang Dinh 
Published: June 2021

Panax bipinnatifidus Seem. belonging to the family Araliaceae has been used as a folk medicine in Viet Nam. Our ongoing study on bioactive compounds from Panax bipinnatifidus Seem. collected in Sapa, Lao Cai resulted in the isolation of two saponins together with the well-known saponin Stipuleanoside R2. Their structures were identified as 3-O-β-D-glucopyranosyl-(1→3)-β-D-glucuronopyranosyloleanolic acid (1) and Stipuleanoside R1 (2) based on NMR spectroscopic data as well as comparison with the literature data. For the first time, 3-O-β-D-glucopyranosyl-(1→3)-β-D-glucuronopyranosyloleanolic acid (1) was found in genus Panax. On biological screening, the crude extract and the principal saponin, stipuleanoside R2 showed weak inhibitory effect on markedly nitric oxide production in lipopolysaccharide-treated RAW 264.7 cells.
Potential Mortalin-p53 complex abrogation of ent-kaurane diterpenoids from Croton tonkinensis revealed by homology modeling and docking simulation
Authors: PHAM Quan Minh , HA Hai Viet , DO Nghi Huu , DAO Hung Viet , VU Thu Le Thi 
Published: June 2021

Seven ent-kaurane diterpenoids from Croton tonkinensis were tested for cytotoxicity against human HCC HepG2 cell line. The abrogation of mortalin-p53 interaction represent an original anticancer therapeutic approach. Teritary structure of protein mortalin was constructed using Protein Structure Prediction Server and crystal structure of p53 was selected from Protein Data Bank involving mortalin-p53 binding domain. Molecular docking studies revealed that the interaction with protein mortalin is more prominent than p53 compound 5 and 1 as the most two potential mortalin-p53 binding inhibitors based on binding free energy and interacting residues analysis.
CHEMICAL COMPOSITION OF THE ESSENTIAL OIL FROM LEAVES OF CALLICARPA ARBOREA ROXB. GROWING IN VIETNAM
Authors: Nguyen Hung Huy , Do Dai Ngoc , Satyal Prabodh , Nguyen Chung Thanh , Bui Nguyen Van , Vu Hien Thi , N Setzer William 
Published: June 2021

The essential oil from the leaves of Callicarpa arborea Roxb. growing wild in Vietnam, was obtained by hydrodistillation and analyzed by gas chromatography – mass spectrometry. The major constituents of leaves of C. arborea were β-selinene (23.9%), ar-turmerone (17.5%) and α-copaene (8.9%), with lesser concentrations of caryophyllene oxide (4.9%) and ar-turmerol (3.9%). The chemical composition of this essential oil sample is being reported for the first time.
DIRECT NUMERICAL SIMULATION STUDY OF WATER DROPLETS FREEZING ON A HORIZONTAL PLATE
Authors: Vu Truong V. , Pham Binh Duy , Nguyen Lien V.T. , Nguyen Cuong , Nguyen Hoe , Nguyen Vinh , Vu Hung 
Published: June 2021

We present the numerical results of the solidification process of water droplets on a cold plate with different wetting angles. The numerical method used is an axisymmetric front-tracking technique. The water droplets are assumed as a spherical cap and placed on the cold plate which is kept at a subfreezing temperature. At the end of solidification, we obtain a small protrusion shape at the top of the frozen water droplet and its height is also higher than that of the initial water droplet. The frozen water droplets are also compared with the corresponding experimental ones reported in the literature.
DEVELOPING AND VALIDATING A GT-SUITE BASED MODEL FOR A SECOND GENERATION COMMONRAIL SOLENOID INJECTOR
Authors: Nguyen Dat Xuan , Nguyen Vu Hoang , Pham Phuong Xuan 
Published: June 2021

Injection profiles, containing important parameters like injection rate, directly affect the spray structure, fuel-air mixture quality, and as such the physical and chemical processes occurring in the IC engine’s combustion chamber. Therefore, injection profiles are one of the keys to improving power, thermal efficiency and minimizing the emission for IC engines. In this paper, a GT-Suite - based simulation model for a second generation solenoid commonrail injector typically utilized in Hyundai 2.5 TCI-A diesel engines, has been successfully developed and validated. The validation is done by using experimental data are acquired by a Zeuch’s method-based Injection Analyzer (UniPg STS) in University of Perugia, Italy. The calibration data is measured over a wide range of rail pressure and energizing time (ET) corresponding to the engine operating conditions. The results show that the injector model developed here is reliable and suitable for examining the injector’s hydraulic characteristics. The difference in start of injection values obtained through experiment and simulation is only about 15 µs. The total injection volumes obtained through experiment and simulation under ET > 0.8 ms is less than 10 % while the difference is quite high under ET < 0.8 ms and high rail pressure (up to 34.5 %).
Measuring the Occupational Impact of AI: Tasks, Cognitive Abilities and AI Benchmarks
Authors: Tolan Songül , Pesole Annarosa , Martínez-Plumed Fernando , Fernández-Macías Enrique , Hernández-Orallo José , Gómez Emilia 
Published: June 2021

In this paper we develop a framework for analysing the impact of Artificial Intelligence (AI) on occupations. This framework maps 59 generic tasks from worker surveys and an occupational database to 14 cognitive abilities (that we extract from the cognitive science literature) and these to a comprehensive list of 328 AI benchmarks used to evaluate research intensity across a broad range of different AI areas. The use of cognitive abilities as an intermediate layer, instead of mapping work tasks to AI benchmarks directly, allows for an identification of potential AI exposure for tasks for which AI applications have not been explicitly created. An application of our framework to occupational databases gives insights into the abilities through which AI is most likely to affect jobs and allows for a ranking of occupations with respect to AI exposure. Moreover, we show that some jobs that were not known to be affected by previous waves of automation may now be subject to higher AI exposure. Finally, we find that some of the abilities where AI research is currently very intense are linked to tasks with comparatively limited labour input in the labour markets of advanced economies (e.g., visual and auditory processing using deep learning, and sensorimotor interaction through (deep) reinforcement learning).
This article appears in the special track on AI and Society.
Torsion-shear behaviour at the interfaces of rigid interlocking blocks in masonry assemblages: experimental investigation and analytical approaches
Authors: Casapulla Claudia , Mousavian Elham , Argiento Luca , Ceraldi Carla , Bagi Katalin 
Published: June 2021

AbstractIncreasing interest has recently been devoted to interlocking blocks/interfaces capable to enhance the sliding resistance of masonry joints to external forces. In this framework, this paper deals with the assessment of the torsion-shear capacity of the contact interface between the lock and the main body of an interlocking block, assumed to have a cohesive behaviour. The interlocking block is a rigid unit which, on its faces, have square cuboidal locks keeping the adjacent/overlapped blocks together and preventing blocks from sliding. Two numerical approaches and a novel ad hoc experimental investigation are proposed to simulate the torsion-shear behaviour by applying eccentrical shear forces to the lock. First, concave, convex and corrected concave formulations provided by the literature for assemblages of rigid blocks with conventional planar joints are extended to model the interlocking block behaviour. Then, according to a second approach based on the discrete element method, the concave-shaped interlocking block is modelled by convex polyhedrons representing the lock and the main body of the block, considered as individual rigid units stacked over each other with a cohesive contact in between. A novel experimental investigation on the limiting pure shear and torsion-shear combinations at the lock interface made of cohesive material is also presented. Two different mortars were chosen to make the specimens, which were casted using 3D printed moulds, and different test configurations were set up to simulate shear and torsion-shear failures. The analytical and numerical results are compared with each other and against the experimental ones, with interesting remarks on the application of the different approaches.
Pycheron: A Python-Based Seismic Waveform Data Quality Control Software Package
Authors: Aur Katherine Anderson , Bobeck Jessica , Alberti Anthony , Kay Phillip 
Published: June 2021

AbstractSupplementing an existing high-quality seismic monitoring network with openly available station data could improve coverage and decrease magnitudes of completeness; however, this can present challenges when varying levels of data quality exist. Without discerning the quality of openly available data, using it poses significant data management, analysis, and interpretation issues. Incorporating additional stations without properly identifying and mitigating data quality problems can degrade overall monitoring capability. If openly available stations are to be used routinely, a robust, automated data quality assessment for a wide range of quality control (QC) issues is essential.To meet this need, we developed Pycheron, a Python-based library for QC of seismic waveform data. Pycheron was initially based on the Incorporated Research Institutions for Seismology’s Modular Utility for STAtistical kNowledge Gathering but has been expanded to include more functionality. Pycheron can be implemented at the beginning of a data processing pipeline or can process stand-alone data sets. Its objectives are to (1) identify specific QC issues; (2) automatically assess data quality and instrumentation health; (3) serve as a basic service that all data processing builds on by alerting downstream processing algorithms to any quality degradation; and (4) improve our ability to process orders of magnitudes more data through performance optimizations. This article provides an overview of Pycheron, its features, basic workflow, and an example application using a synthetic QC data set.
Haematological Traits of Induced Hypovolemic Large White Yorkshire Piglets as Affected by Feeding them Milk of Pantja Goats and Black Badri Cows
Authors: Dineshkumar M. , Singh D.V. , Rastogi S.K. , Kumar Sanjay , Singh S.K. , Kumar Anil 
Published: June 2021

Background: Pig is recognized as an advantageous non-rodent animal model within a large number of biomedical research areas and of xenotransplantation of animal organs into humans. People prefer taking goat milk during dengue fever like conditions for recovery from low blood constituents, particularly the blood platelets, without any scientific proof. Methods: Haemoglobin, Erythrocyte Sedimentation Rate (ESR) and blood platelets count were studied in 2.5 months old 18 experimentally induced hypovolemic Large White Yorkshire (LWY) piglets at CVASc., GBPUAT, Pantnagar after feeding them milk of Pantja goats and black Badri cows over a period of 30 days during Oct.–Nov. 2019 and May-June 2020. Hypovolemia in piglets was achieved by withdrawing their 15% of total estimated blood volume (@ 7.5% in each time on day 1st and 3rd of experiment), followed by providing them with milk, which was double the amount of blood withdrawn, for 30 days. Control group (T1) piglets (6 no.) were maintained on basal diet, whereas group T2 and T3 piglets were given milk of Pantja goats and black Badri cows, respectively. Blood samples for testing were collected on 1st, 3rd, 7th, 15th and 30th day. Result: Average normal blood picture of weaned LWY piglets for haemoglobin (g/dl), ESR (mm/hr) and platelets count (105 cells/ mm3) was 11.36 ± 0.20, 10.00± 2.01, 3.1767 ± 0.2577, respectively. For haemoglobin and ESR, the values on testing days and the overall values for group T1, T2 and T3 piglets did not show any significant variation. However, the pooled values for haemoglobin were significantly different (P less than 0.01) on various testing days, being higher on day 1st and 30th than on 3rd, 7th and 15th day, implying that normal haemoglobin level was regained on 30th day of hypovolemia. The pooled values for ESR were significantly different (P less than 0.05) on various testing days, being higher on day 1st and 3rd only, which may be due to simultaneous increase in total erythrocyte counts. Overall mean platelets count (x105 cells/ mm3) for LWY piglets was 3.2570± 0.0890 and their values in group T1, T2 and T3 piglets were 3.0983±0.1675, 3.0820±0.1490 and 3.5907±0.1885, respectively, being significantly higher (P less than 0.05) for black Badri cow milk fed group piglets. This may imply usefulness of black Badri cow milk over Pantja goat milk in improving blood platelets count in human, considering pig a good animal model for human within a large number of biomedical researches.
The influence of thermodynamic parameters on alkaline activator of geopolymers and structure of geopolymers
Authors: Ivanović Marija , Nenadović Snežana , Pavlović Vera P , Radović Ivona , Kijevčanin Mirjana , Pavlović Vladimir B , Kljajević Ljiljana 
Published: June 2021

In this research, the starting precursor material is metakaolin, which was obtained by calcining domestic kaolinite clay. Thermodynamic parameters: densities, viscosities, speed of sound and refractive index of four series of alkaline activatorswere determined over the temperature range from 15 to 60oC of process of geopolymerization. The samples were characterized by X-ray diffraction (XRD), FTIR and Raman Spectroscopy, Scanning Electron Microscopy (SEM), and Energy-Dispersive X-Ray (EDX) Spectroscopy. Results of FTIR analysis correlated with results of Raman Spectroscopy. Due to the polymerization process the changes in the phonon spectrum is confirmed. The different concentrations of activators do not change notably the Si/Al ratio.
STUDY OF THE UTILIZATION OF PALM OIL INDUSTRY LIQUID WASTE
Authors: Fitria An Nisa , Gunawan Vandhie Satyawira , Mardiah Mardiah 
Published: June 2021

Palm oil is one of the plantation crops that have high economic value and is growing rapidly. The wider the area of oil palm plantations in Indonesia, the more palm oil mills will process palm fresh fruit marks and produce waste from processed palm oil, namely solid waste and liquid waste. Each tonne of fresh fruit bunches (FFB) processed at the plant will potentially leave waste of about 23% empty palm oil, 4% wet decanter solid, 6.5% shell, 13% fiber, and 50% liquid waste. This review will discuss the utilization of palm oil mill liquid waste (LCPKS) which is organic material that still contains many benefits such as nutrients, therefore the application of liquid waste is an effort to recycle some of the nutrients (recycling nutrients) which is followed by harvesting fresh fruit bunches (FFB) from oil palm so that it will reduce the cost of fertilization which is classified as very high for oil palm cultivation. During the processing of oil palm fruit into palm oil in the palm oil industry, the remaining process is obtained in the form of liquid waste. If done properly, the liquid waste of the palm oil industry is considerable potential and can increase the added value of waste itself.Keywords: liquid waste industry, palm oil, utilization
ISOLATION OF CLOVE ESSENTIAL OIL BY FERMENTATION PROCESS
Authors: Ainiyah Khurotul , Andriyani Fita , Soemargono Soemargono , Erliyanti Nove Kartika 
Published: June 2021

Clove essential oil is processed product of clove leaves which is used as perfumes and medicines. In general, the method used to extract clove leaf essential oil is the steam distillation method. This method has not maximized the yield essential oils produced because a lot of essential oils are still trapped in plant tissues. Modification of the essential oil isolation methods to produce more yields needs to be done, one of which is the fermentation method with the help Rhizopus oligosporus before the distillation process is carried out. The fermentation method is able to destroy the oil tissues on the leaves using enzymes produced by rhizopus oligosporus. The aims of this study were to isolate the essential oil clove leaves and look for the effect of the mass and fermentation time on the yield and content of clove leaf essential oil compounds produced. The results showed that the isolation essential oils using fermentation methods was successfully carried out, the mass and fermentation time had a significant influence on the yield and content of essential oil chemical compounds. The best result was obtained at a mass of 35 grams with a fermentation time of 36 hours with a yield 0.32% and the content eugenol, caryopillene compounds obtained respectively at 93.43% and 2.28%.