Miracle-dz/UniFAR-FTUs huggingface dataset:
Modelling risk spillover between oil price shocks and stock market returns in the BRICS

Overview With the rapid development of futures, options and other derivatives, oil market has become more financialized which is involved into the global financial system. It means oil price changes are not only exogenous shocks to macroeconomic variables, but also exposed to systemic financial risk with other financial markets. Especially, speculative activities and capital flows globally have strengthened their comovement. The 2008 global financial crisis presents a good interpretation that both stock market and oil market have experienced a significant turbulence almost simultaneously affected by the global economic recession. Therefore, research on the relationship between oil price changess and stock market returns has received a increased concern by researchers and market investors, which can provide an useful anticipation for portfolio strategies and risk avoidance. However, following Kilian’s (2009) work, not all oil price shocks are alike. It’s because the causes of oil price fluctuations are different. For example, the impact of hurricanes on oil prices is supply-side shock, the global financial crisis impact on oil prices is aggregate demand shock and the shock from Libyan war is precautionary demand shock (Ji and Guo, 2015). Obviously, different origins of oil price shocks depict different transmission path of depedence structure and risk spillover between oil price shocks and stock market returns. The most previous literatures often follow Kilian’s (2009) frawework and employ SVAR to model the linear and static relationship between oil price shocks and its influences on stock market returns. They ignored the importance of examining the relationship between oil prices and stock markets in a time-varying and nonlinear environment. This paper extends the previous studies and tries to combine dynamic copula models with SVAR model to caputure the dynamic dependence and risk spillover between all oil price shocks and stock market returns in the BRICS countries by measuring upside and downside CoVaR. The paper is organised as follows: After the introduction the second section proposes the research methodology. Section 3 conducts the empirical analysis and the last Section concludes the paper.
MACRONUTRIENT, SOIL ORGANIC CARBON, AND EARTHWORM DISTRIBUTION IN SUBTROPICAL PASTURES ON AN ANDISOL WITH AND WITHOUT LONG-TERM FERTILIZATION

Pasture fertilization affects plant growth and animal production, and it may influence the redistribution and cycling of nutrients excreted in dung and urine. Kikuyugrass (Pennisetum clandestinum Hochst. ex Chiov.) pastures on a high organic carbon (C) Typic Hydrudand soil with and without (control) annual nitrogen (N) and periodic phosphorus (P) and potassium (K) fertilizations were stocked with Hereford and crossbred cattle (Bos taurus) for 33 years. The pastures were divided into 1.2-ha paddocks for rotational stocking after the 15th year. Selected fertilized paddocks that were uniformly managed over the years were paired with control paddocks to determine management effects on soil organic C; soil and plant N, P, and K; and earthworm distribution. Responses were assessed using a zonal sampling procedure based on distance from the waterer because the paddocks lacked shade. Soil organic C, organic N, and organic P did not statistically differ between managements or zones in any horizon. Relative to the control, however, an apparent recovery of 25% of the total N applied to the fertilized paddocks was obtained as soil organic N within the 80 cm profile depth examined. Inorganic N (NH4-N + NO3-N) was greater in the Ap1 and Bw1 horizons of fertilized paddocks, and there was a trend in the Ap1 horizon toward greater concentrations within 15 m of the waterer. Additionally, substantial inorganic P accumulated within 30 m of the waterers in the Ap1 and Bw1 horizons of fertilized paddocks while minimal P accumulation occurred within 15 m of the waterer in control paddocks. The magnitude of K accumulation near waterers was also considerably greater in the Ap1 horizon of fertilized paddocks. It is suggested that fertilization increases the magnitude of P and K accumulation near waterers due to the combination of increased forage P and K concentrations and pasture carrying capacity. Management and zone effects for forage N, P, and K tended to follow patterns relatively similar to the soil Ap1 horizon data for the inorganic forms of these nutrients. Earthworm populations did not differ among zones, but populations in fertilized paddocks were double those of control paddocks.
The Role of Cholinergic Cortical Modulation from the Nucleus Basalis Magnocellularis in Visual and Olfactory Attention using the 5-Choice Serial Reaction Time Task

To date, research using rodent models has primarily dealt with the visual aspects of attention, while in the present research, we examined neurochemical modulation of attentional processes using both a visual and an olfactory five choice serial reaction time task (5-CSRTT). The nucleus basalis magnocellularis (NBM) in the basal forebrain is the primary source of cortical cholinergic input, which is thought to have an important modulatory effect on rat attentional processes. Thus, after successful acquisition of the task, the rats were subjected to either a cholinergic immunotoxic or sham lesion surgery of the NBM. Cortical cholinergic deafferentation of the cortical mantle was induced by bilaterally infusing 0.2 μg/μl of the cholinergic immunotoxin, 192 IgG-saporin, into the NBM (saporin-lesion). Reduction of cortical cholinergic modulation led to comparable attentional impairments in the saporin-lesion group, relative to the sham-lesioned group, on both visual and olfactory versions of the 5-CSRTT.
Magnetic Graphene Oxide Anchored Sulfonic Acid as a Novel Nanocatalyst for the Synthesis of N-aryl-2-amino-1,6-naphthyridines

Magnetic graphene oxide functionalized with sulfonic acid (Fe3O4-GO-SO3H) was used as a new recyclable nanocatalyst for one-pot synthesis of N-aryl-2-amino-1,6-naphthyridine derivatives under solvent free conditions. The catalyst could be easily recovered from the reaction mixture by an external magnet and reused without significant decrease in activity even after 4 runs. This nanocatalyst exhibited better activities to other commercially available sulfonic acid catalysts.
Mechanisms of Action of Mixed Solid-Liquid Antifoams. 1. Dynamics of Foam Film Rupture

Antifoams (usually consisting of a mixture of hydrophobic solid particles and oils) are widely used in different technological applications to prevent the formation of excessive foam. Uncertainty still exists in the literature about the actual mechanisms by which these substances destroy the foam. To elucidate this problem, we have performed microscopic observations on the process of foam film destruction by means of a high-speed camera. Horizontal and vertical foam films (obtained from solutions of the surfactant sodium dioctyl sulfosuccinate) were studied in the presence of antifoam particles containing silicone oil and hydrophobized silica. The observations show that in this system the antifoam particles destroy the foam lamella by the formation of unstable oil bridges, which afterward stretch and eventually rupture, due to uncompensated capillary pressures across the different interfaces. These bridges can be formed either from initially emulsified antifoam droplets, which enter both surfaces of the f.
Millimeter-wave spectroscopy of vibrationally excited ground state alkaline-earth hydroxide radicals (X 2Σ+)

Pure rotational spectra of the alkaline‐earth monohydroxides have been recorded for vibrationally excited states (0 1 0), (0 2 0), (0 3 0), and (1 0 0) of the ground electronic state (X 2Σ+) using millimeter‐wave absorption spectroscopy. The radicals MgOH, CaOH, SrOH, and BaOH were studied. The data for CaOH, SrOH, and BaOH were analyzed with a linear 2Σ+ model, but with the addition of two terms to account for contamination of the v2=1 2Π and v2=2 2Δ vibronic levels with 2Π and 2Δ electronic states. The data for MgOH, however, did not fit well to this linear model and is additional evidence that this species is quasilinear.
A Novel Electrochemical Immunosensor for Prostate-Specific Antigen Based on Noncovalent Nanocomposite of Ferrocene Monocarboxylic Acid with Graphene Oxide

A novel electrochemical immunosensor was developed for the determination of prostate-specific antigen based on immobilization of appropriate antibodies on gold nanoparticles and a poly-(2,6-pyridinediamine) modified electrode. The nanocomposite of ferrocene monocarboxylic acid hybridized graphene oxide was prepared by a π-π stacking interaction and was used as the electrochemical probe. A sandwich-type complex immunoassay was applied with polyclonal prostate-specific antigen antibodies labeled with the nanocomposite of ferrocene monocarboxylic acid hybridized graphene oxide. In order to improve the sensitivity, a potentiostatic method was used to reduce graphene oxide. Cyclic voltammetry and differential pulse voltammetry were employed to characterize the assembly process and the performance of the immunosensor. Under optimal conditions, the peak current of the immunosensor increased with concentration, showing a linear relationship between the peak current and the logarithm of the prostate-specific antigen concentrations in a wide range of 2.0 pg mL−1 to 10.0 ng mL−1 with a low detection limit of 0.5 pg mL−1. The immunosensor was used for the determination of prostate-specific antigen in serum.
Determination of the complanar geometric lattice parameters of monocrystals with high precision

A measuring method is presented which allows to determine the complanar geometric lattice parameters (the amounts of two unit cell vectors and the angle between the both unit cell vectors) of monocrystals with high precision at one crystal point and in one measurement cycle. The efficiency of the method is demonstrated at measurements of two quartz monocrystals. Ein Verfahren zur hochprazisen Messung komplanarer geometrischer Gitterparameter, d. h. der Betrage von zwei Basisvektoren der Elementarzelle und des von beiden Basisvektoren eingeschlossenen Winkels, an einem Probenort und in einem Mesdurchlauf wird vorgestellt. Die Leistungsfahigkeit des Verfahrens wird am Beispiel der Messung von zwei Quarzkristallen demonstriert.
Factors Affecting the Performance of Capillary Isoelectric Focusing in Dynamically Coated Capillaries Using Polyethylene Oxide Polymer

Abstract A simple, robust and reproducible capillary isoelectric focusing method using dynamically coated fused silica capillaries was developed. Simultaneous focusing and mobilization was successfully carried out using the hydrophilic polymer polyethylene oxide (PEO), which was added during sample preparation. The effects of preconditioning and anolyte and catholyte concentrations on the resolution and reproducibility of the method were optimized. Statistical screening of the significance of the effects of pressure, voltage, PEO concentration, and molecular weight on the efficiency of dynamic coating was carried out. Full-factorial design and analysis of variance (ANOVA) were used in order to determine the significance of each variable on the performance of the dynamic coat. Three response variables were selected to evaluate the method performance: migration time of a basic protein marker, migration time of an acidic protein marker, and difference in migration time between both markers. An empirically determined second order polynomial was employed to describe the relationship between the migration time and the isoelectric point under the experimental conditions studied in order to validate the method performance. The method was used under non-denaturing conditions to resolve a mixture of four standard proteins having isoelectric points covering a wide pH range (pH 3–11).
STRUCTURE, CHEMISTRY, AND CLUMPING IN THE NGC-2071 (NORTH) MOLECULAR CLOUD

We have carried out a study of the NGC 2071 (North) molecular cloud in the 3 mm wavelength transitions of CO, 13 CO, C 18 O, CS, and HCO + using the FCRAO 14 m telescope. We find that the distribution of CS and C 18 O, two tracers that are widely used to trace dense gas in molecular clouds, are very different, and that they both differ appreciably from the previously published distribution of NH 3
Effect of Rotor Shape on Particle Composite Process by a High-Speed Elliptical-Rotor-Type Mixer.

高速楕円ロータ一型混合機による核粒子表面への微粒子複合化に着日し，ロ-タ-形状が複合化に及ぼす影響を検討した．その結果，複合化過程はロ-ター形状によって大きく影響されることが分かつた．この原因を，粒子要素法（PEM）による核粒子の運動シミュレーションにより解析し，ロ-タ-と核粒子間の平均接触力の違いによって，結果を定性的に説明できた．
Effects of Ambient Oxygen Concentration on Soot Temperature and Concentration for Biodiesel and Diesel Spray Combustion

AbstractAmbient oxygen concentration, a key variable directly related to exhaust gas recirculation (EGR) levels in diesel engines, plays a significant role in particulate matter (PM) and nitrogen oxides (NOx) emissions. The utilization of biodiesel in diesel engines has been investigated over the last decades for its renewable characteristics and lower emissions compared to diesel. In an earlier work, we demonstrated that the soot temperature and concentration of biodiesel were lower than diesel under regular diesel engine conditions without EGR. Soot concentration was quantified by a parameter called KL factor. As a continuous effort, this paper presents an experimental investigation of the ambient oxygen concentration on soot temperature and KL factor during biodiesel and diesel spray combustion. The experiment was implemented in a constant volume chamber system, where the ambient oxygen concentration varied from 21 to 10% and the ambient temperature was kept to 1,000 K. A high speed two-color pyrometry.
Measurement of diffusion coefficients in supercritical carbon dioxide and correlation with the equation of Wilke and Chang

Diffusion coefficients of acetone, benzene, naphthalene, 1,3,5-trimethylbenzene, phenanthrene, pyrene, and chrysene have been measured by a chromatographic broadening technique in an open capillary tube (950 x 0.103 cm) filled with pure supercritical carbon dioxide or, in the case of benzene, with CO/sub 2/-methanol mixtures ranging from 0 to 100% in methanol. In pure supercritical CO/sub 2/, diffusion coefficients decrease when density increases; they increase linearly vs. the reciprocal of the viscosity; a linear relationship exists between the logarithms of the diffusion coefficients and the molar volumes with a slope of 0.6. Finally, in the range 0.6-0.9 g cm/sup -3/, the Wilke and Chang equation for the calculation of diffusion coefficients is valid for supercritical CO/sub 2/. For methanol-CO/sub 2/ mixtures there is no discontinuity of the diffusion coefficient of benzene when the methanol content varies from 0 to 100%. In the usual supercritical chromatographic conditions with a methanol content less than 10%, diffusion coefficients are at least 4 times higher than in pure methanol.
DNA-stabilized silver nanoclusters with guanine-enhanced fluorescence as a novel indicator for enzymatic detection of cholesterol

A novel silver nanocluster is synthesized using a DNA template with short guanine at the 3′-end of a DNA scaffold to enhance the fluorescence intensity. The obtained DNA-stabilized silver nanoclusters (G-DNA-Ag NCs) are found to exhibit a strong red fluorescence at 605 nm and its fluorescence can be sensitively quenched by H2O2. This allows us to develop a new enzymatic method for fluorescent detection of cholesterol through oxidation by cholesterol oxidase which can generate H2O2. The present method is convenient without the need for complicated operations, and demonstrates desirable selectivity with no interferences from species such as ascorbic acid, glucose and urea. It shows a linear detection range for cholesterol from 0.2 to 200 μM with a detection limit of 0.15 μM.
Removal of Hydrogen Sulfide on Composite Sewage Sludge-Industrial Sludge-Based Adsorbents

The sludge-based adsorbents were obtained either from mixtures of sewage sludge, waste oil sludge, and metal sludge or single components by carbonization at 650 °C in an inert atmosphere. The materials were used as media to remove hydrogen sulfide at room temperature in the presence of moisture. The initial and exhausted adsorbents after the breakthrough tests were characterized using sorption of nitrogen, thermal analysis, XRD, ICP, and surface pH measurements. Although on all materials hydrogen sulfide is oxidized to elemental sulfur, exceptionally good performance is obtained on the waste oil sludge-based adsorbent. This is attributed to the combined effects of surface chemistry and porosity. High pore volume of the waste oil sludge-based adsorbent provides space to store 30 wt % elemental sulfur formed when hydrogen sulfide undergoes oxidation on the surface. Mixing sludges and carbonization of their mixtures result in adsorbents whose capacity, although smaller than that for the single-component wast.
On the Influence of Surfactant Incorporation during Electroless Nickel Plating

The effects of surfactants on the dynamics and characteristics of plain and composite electroless nickel plating (ENP) are highlighted and discussed herein. An outline of the rudiments of surfactants and some underlying selection criteria is presented at the outset, before emphasis is laid on the salient benefits of introducing such external agents during the plating process. Evidence suggests that their influence on key coating characteristics such as the rate of deposition, structure, corrosion resistance, and the degree of second-phase particle incorporation into the nickel matrix is significant, and depending on the nature and concentration of surfactant employed, can be of immense value to the system.
The condensed chemical dictionary

Extensively revised, enlarged, and updated edition of the standard chemical dictionary which has filled the needs of scientists and students since 1919. Provides short precise definitions, formulas of compounds, their properties, uses, shipping regulations, grades, and similar information. Arrangement is alphabetical with exceptions for organic prefixes and numbered compounds; abbreviations are explained. Lists 571 manufacturers, very many new trademarks, periodic chart of the elements (103). An indispensable reference tool for any reference library with scientific literature. The authors are at State Col lege, Pa. Contents: Publisher's preface. Numerical list of manufacturers. Alphabetical list of manufacturers. Shipping regulations. Editors' statement. Safety information; warning and labels. Trademarks. Explanation of arrangement. Periodic chart of the elements. -- AATA
Arm-Stroke Descriptor Variability during 200-m Front Crawl Swimming

The present study aimed to explore the variability of the arm-stroke temporal descriptors between and within laps during middle-distance swimming event using IMMUs. Eight male swimmers performed a 200-m maximum front-crawl in which the inter-lap and intra-lap variability of velocity, stroke rate, stroke-phases duration and arm-coordination index were measured through five units of IMMU. An algorithm computes the 3D coordinates of the wrist by means the IMMU orientation and the kinematic chain of upper arm biomechanical model, and it recognizes the start events of the four arm-stroke phases. Velocity and stroke rate had a mean value of 1.47 ± 0.10 m·s−1 and 32.94 ± 4.84 cycles·min−1, respectively, and a significant decrease along the 200-m (p < 0.001; η2 = 0.80 and 0.47). The end of each lap showed significantly lower stroke rate compared to the start and the middle segment (p < 0.05; η2 = 0.55). No other significant inter-lap and intra-lap differences were detected. The two main findings are: (i) IMMUs technology can be an effective solution to continuously monitor the temporal descriptors during the swimming trial; (ii) swimmers are able to keep stable their temporal technique descriptors in a middle-distance event, despite the decrease of velocity and stroke rate.
Direct determination of dissolved cobalt and nickel in seawater by differential pulse cathodic stripping voltammetry preceded by adsorptive collection of cyclohexane-1,2-dione dioxime complexes

A highly sensitive voltametric technique was developed for the direct determination of cobalt and nickel in seawater at picomolar and nanomolar concentrations, respectively. Cyclohexane-1,2-dione dioxime (nioxime) complexes of Co(II) and Ni(II) were concentrated from 10 mL of sample onto a hanging mercury drop electrode by controlled adsorption and the current resulting from reduction of Co(II) and Ni(II) was measured by differential pulse cathodic stripping voltametry. Detailed experiments were conducted to determine the optimal ligand type and concentration, buffer type and concentration, pH, and adsorption potential. Maximum sensitivity was obtained by using a nioxime concentration of 1 x 10/sup -4/ m, a HEPES buffer concentration of 0.03 m, a solution pH of 7.6, and an adsorption potential of -0.6 V. Replicate analyses of seawater reference materials yielded excellent agreement with certified values. Analytical precision for Co and Ni at coastal and open ocean concentrations was approximately +/-5% relative standard deviation. Detection limits for Co and Ni depend upon reagent blanks and are 6 pM and 0.45 nM, respectively, for 15-min adsorption periods.
Population-Specific ACE2 Single-Nucleotide Polymorphisms Have Limited Impact on SARS-CoV-2 Infectivity In Vitro

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), employs host-cell angiotensin-converting enzyme 2 (ACE2) for cell entry. Genetic analyses of ACE2 have identified several single-nucleotide polymorphisms (SNPs) specific to different human populations. Molecular dynamics simulations have indicated that several of these SNPs could affect interactions between SARS-CoV-2 and ACE2, thereby providing a partial explanation for the regional differences observed in SARS-CoV-2 infectivity and severity. However, the significance of population-specific ACE2 SNPs in SARS-CoV-2 infectivity is unknown, as no in vitro validation studies have been performed. Here, we analyzed the impact of eight SNPs found in specific populations on receptor binding and cell entry in vitro. Except for a SNP causing a nonsense mutation that reduced ACE2 expression, none of the selected SNPs markedly altered the interaction between ACE2 and the SARS-CoV-2 spike protein (SARS-2-S), which is responsible for receptor recognition and cell entry, or the efficiency of viral cell entry mediated by SARS-2-S. Our findings indicate that ACE2 polymorphisms have limited impact on the ACE2-dependent cell entry of SARS-CoV-2 and underscore the importance of future studies on the involvement of population-specific SNPs of other host genes in susceptibility toward SARS-CoV-2 infection.