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Study question What is the appropriate suction pump pressure for oocyte retrieval in terms of oocytes and embryos quality? Summary answer The aspiration pressure of 150mmHg had a significantly higher number of oocytes retrieved compared with 120mmHg, but the oocyte quality and embryo quality were comparable. What is known already There is no conclusion on the optimal aspiration pressure level for oocyte retrieval in controlled ovarian stimulation (COS), and a variety of pressures between 100 and 200 mmHg are used, often based on manufacturer’s instructions. Study design, size, duration A retrospective analysis was performed on a total of 211 COS cycles from September 2019 to December 2021 in a single tertiary center. The analysis was performed on patients who underwent COS for the purpose of infertility treatment. Participants/materials, setting, methods 110 cycles were included in the 120 mmHg pressure group and 101 cycles were included in the 150 mmHg pressure group. Age, AMH, antral follicle count (AFC), the proportion of ICSI, the number of retrieved oocytes, the number of MII oocytes, MII rate, degeneration rate on day 1, and the number of embryos on day 3 were compared between the two groups. Variables such as Age, AMH, and AFC were corrected using analysis of variance. Main results and the role of chance The number of retrieved oocytes was significantly higher in the 150 mmHg group compared to the 120 mmHg group (10.3 vs. 8.4, p = 0.016). Neither the number of MII oocytes nor the MII rate was significantly different between the two groups (6.1 vs. 5.5, p = 0.509 and 67.2% vs. 73.4%, p = 0.437 respectively). The degeneration rate on day 1 and the number of embryos on day 3 were also not significantly different between the two groups (6.2% vs. 4.4%, p = 0.282 and 5.7% vs. 4.7%, p = 0.109 respectively). Limitations, reasons for caution Since this study analyzed the appropriate pump pressure for oocyte retrieval in infertile patients, caution is needed in extending the study results to patients undergoing oocyte retrieval for the purpose of fertility preservation. Wider implications of the findings The results of this study revealed that oocyte collection could be efficiently performed without damaging the oocytes even with a higher aspiration pressure of 150 mmHg. Trial registration number Not applicable

The Mn-Zn ferrite nanoparticles with a spinel structure were successfully prepared by using chemical co-precipitation method. The formed magnetic ferrite particles were coated on the surface of Fe-6.5 wt%Si alloy particles with the epoxy resin to prepare the powder core. The influence of magnetic ferrite insulation on the magnetic properties of the powder core was studied. Insulating with a moderate quantity of ferrite was found to improve the effective permeability and the loss of the powder core, while the inadequate insulation and the excessive insulation with ferrite led to the rapid growth of the eddy-current loss at high frequency and the remarkable decrease of the effective permeability, respectively. The effective demagnetizing field determined by the core’s density and the magnetic nature of the ferrite were proposed to be the main causes of the variation of the core’s magnetic performance. Loss separation fitting revealed that the hysteresis loss is much higher than the eddy-current loss for the core measured at the frequency lower than 120 kHz. This suggested that improving the effective permeability and the loss of the powder core in low-frequency range should focus on the means of reducing the effective demagnetizing field.

Four new deep ultraviolet (DUV) borates Li7Na2KRb2B12O24, Li7.35Na2.36K1.50Cs0.78B12O24, Li6.97Na2.63K1.24Cs1.15B12O24, and Li7.27Na2.67Rb2.06B12O24 have been produced by high temperature solution method in open air. The structural analysis suggests that they all crystallize in the same trigonal space group R 3 ¯ (No. 148), and possess the identical isolated B12O24 groups. Structural comparison among alkali-metal borates with BnO2n in their chemical formulas have been discussed. In addition, infrared spectra were used to verify their structural validity. Furthermore, the UV–Vis–NIR diffuse reflectance spectra reveal that they exhibit short cutoff edges below 180 nm (6.88 eV). The first-principles theoretical studies carried out to increase the understanding of electronic structure and linear optical property.

The most useful method for financial market risk management may be Value at Risk (VaR) which estimates the maximum loss amount statistically. The VaR is used as a risk measure for one industry. Many real cases estimate VaRs for many industries or nationwide industries; consequently, it is necessary to estimate the VaR for multivariate distributions when a specific portfolio is established. In this paper, the multivariate quantile vector is proposed to estimate VaR for multivariate distribution, and the Vector at Risk for multivariate space is defined based on the quantile vector. When a weight vector for a specific portfolio is given, one point among Vector at Risk could be found as the best VaR which is called as an alternative VaR. The alternative VaR proposed in this work is compared with the VaR of Morgan with bivariate and trivariate examples; in addition, some properties of the alternative VaR are also explored.

In order to improve the remanence of (Nd, Dy)-Fe-B sintered magnets, we investigated the influence of compaction conditions such as packing density, applied field and green density on the magnetic properties. While the remanence decreased with increasing the packing density and green density, it increased with the increase of the applied field. In addition, XRD analysis revealed that the remanence was enhanced as the degree of powder alignment was improved. The green density was more influential on the remanence than the packing density and applied field.

The thermodynamic behavior of near ground-state isomers of Au 55 clusters are investigated through molecular-dynamic simulations using an n -body effective potential. During relaxation at certain energies, non-reversible structural transitions (from cuboctahedron to icosahedron, and then to disordered configuration) occur well below the melting temperature. We show in this Letter on a picosecond scale the motion of the individual atoms in a cluster during these transformations, demonstrating that the processes involved are either collective distortions of the entire cluster or migration of individual or small groups of atoms. In both cases the cohesive energies of the system go smoothly without any significant barrier during transitions.

Based on the Hadj-Romdhane–Danner model of the chromatographic process, the infinite dilution diffusion coefficients of n -hexane, n -heptane, n -octane and toluene in polyisobutylene (PIB) have been measured at temperatures in the range of 323.2–373.2 K by inverse gas chromatography (IGC). The measured infinite dilution diffusion coefficients for the toluene/PIB system were compared with the diffusivity data at finite concentration determined previously from NMR experimental method by using the Vrentas–Duda free volume theory. The good agreements indicate the IGC method studied in this work is reliable. Moreover, the correlations of the experimental data with the free volume equation were preformed. The correlated results show that the free volume theory is a quite good description of the relationship between the observed solvent diffusion coefficient and temperature.

The Ulleung Basin in the East Sea (Sea of Japan) is a semi-enclosed basin surrounded by shallow sills and straits. Detailed observation of X-radiographs and thin sections of core sediments from the Ulleung Interplain Gap reveals five mud facies: laminated mud, crudely laminated mud, homogeneous mud, bioturbated mud and laminated Mn-carbonate mud. The laminated and homogenous muds were most likely deposited from turbidity currents, whereas the bioturbated and crudely laminated muds were formed by pelagic/hemipelagic sedimentation under oxic and anoxic bottom-water conditions, respectively. The laminated Mn-carbonate mud occurs at the lithologic boundary between the turbidite and hemipelagic laminated mud (last glacial) and the pelagic bioturbated mud (Lateglacial to Holocene). Mn-carbonates were formed at the sediment–water interface, probably reflecting an abrupt change in bottom-water oxygenation caused by sea-level rise during the last deglaciation. Profiles of redox-sensitive elements also support an anoxic to oxic change of bottom-water conditions during this period.

A gas-liquid-solid inverse fluidization airlift bioreactor was proposed by combining advantages of external-loop airlift reactors and inverse fluidized beds. This airlift bioreactor comprises a gas-liquid riser, a gas separator, a liquid-solid inverse fiuidized downcomer and a bottom connector. The effects of the gas velocity and the particle loading on the gas holdup in the riser and the liquid circulation velocity in the loop were investigated. Liquid-solid inverse fluidization in the downcomer was also studied. The gas holdup in the riser was experimentally found to increase with the increase in the particle loading and in the gas velocity. The liquid circulation velocity decreased with the increase in the particle loading whereas it increased with the gas velocity. It was found that the Richardson and Zaki model fitted experimental data of bed expansion of liquid-solid inverse fluidization in the downcomer well. Based on an energy balance, two hydrodynamic models were proposed to predict the liquid circulation velocity in the present bioreactor. It was shown that the present models gave a good fit to experimental data in this bioreactor.

N2O emissions from agricultural, forest and grassland ecosystems in China were in situ measured by closed chamber method, and estimation of total annual N2O emissions from these ecosystems and a technique mitigating N2O emission from agricultural soil were reported. The results showed: (1) the annual emissions of N2O from rice, maize, soybean and wheat field, temperate forest and temperate grassland in China were 1.08–2.99, 0.47–4.51, 1.98, 1.02–2.93, 0.28–1.28 and 0.27–0.61 kg N 2 O – N ha −1 , respectively. The total annual N2O emissions from agricultural, forest and temperate grassland ecosystems in China were estimated as 152.49, 94.10 and 112.13 Gg N, respectively. Industrially co-crystallized ammonium bicarbonate (AB) with dicyandiamide, substituting for ammonium bicarbonate in China, decreased N2O emission significantly from a meadow brown soil in laboratory (80.2% at soil moisture 12% and 40.0% at soil moisture 22%, respectively) and upland field condition (74.0%).

A detailed facies analysis of long piston-core sediments from the Ulleung Basin reveals four mud facies: laminated mud, crudely laminated mud, bioturbated mud, and homogenous mud. The laminated and homogeneous muds were most likely deposited from turbidity currents, whereas the bioturbated and crudely laminated muds were formed by hemipelagic/pelagic sedimentation under well-oxygenated and poorly oxygenated bottom-water conditions, respectively. A detailed analysis of vertical distribution of the mud facies together with a chronostratigraphic framework derived from correlative tephra layers with known eruption ages reveals paleoenvironmental changes during the late Quaternary. During the period between 49 and 23 ka, eustatic lowering of sea level facilitated frequent slope failure, resulting in repeated deposition of fine-grained turbidites on the basin floor. Normal hemipelagic sediments were intensively bioturbated under well-oxygenated bottom-water conditions. During the period between 23 and ∼13 to 11 ka, deposition from turbidity currents continued, but hemipelagic sediments were non-bioturbated under poorly oxygenated bottom water conditions. The bottom-water deoxygenation is attributed to further lowering of sea level during the last glacial period and consequent intensified stratification in the water column by freshwater supply to the nearly isolated sea. Primary laminae preserved in the crudely laminated mud generally exhibit low compositional bimodality in backscattered electron images, which suggests low surface primary productivity and presence of superficial micro-bioturbation. After rapid rise of sea level at ∼13 to 11 ka, the slopes were stabilized and pelagic sedimentation has prevailed under well-oxygenated bottom-water conditions.

The literature data of dilute solution viscosity for binary blend indicate that the intrinsic viscosity of binary polyblend can be obtained from the values of corresponding constituent polymers by using the weighted additive law. This law was also testified by measurement of CS/PEG polyblend in this work. On the basis of it, the α criterion of polymer–polymer miscibility determined by viscosity, proposed by Sun et al., is simplified. Since the revised criterion is a function of three variables: (1) the intrinsic viscosity for polymeric components (2) the weight fraction of polymeric components (3) the difference of the cross Huggins coefficient for polyblend and geometric average of Huggins coefficient for the constituent polymers, it is of more definite physical significance. Furthermore, it was proved that the revised criterion has the same judgment ability as that of the α criterion by using six binary blend systems, i.e. PVC/PMMA, PB(OH)/PBA, PB(OH)/PBMA, PVC/PiBMA, PMMA/PiBMA, PMMA/PiBMA, and three new binary blend systems measured in this work, i.e. PEG-6K/CS, PEG-10K/CS, PEG-20K/CS.

This article briefly investigates the use of Augustine as an authority from the early church in John Calvin’s writings. Calvin frequently referred to and quoted Augustine in his writings. Augustine undoubtedly exerted an influence on Calvin’s views and arguments. This article traces Calvin’s use of Augustine in his writings chronologically as they were published since 1532. In addition, a data analysis provides relevant information in order to argue a scrutinised exposition of Augustine’s influence on Calvin’s thinking. The article does not try to compare the theologies of Augustine and Calvin, nor to establish a theory that would reveal Augustine’s influence on Calvin’s theology. This investigation suggests methodological help for further research in this regard.

High-resolution (3.5 kHz) seismic profiles from the slope of the Korea Plateau, East Sea (Sea of Japan) show an extensive area of slide deposits with prominent slump scars. The sediment displaced from the steep slope (5–7°) is less expansive than massive failure deposits on gradual slopes (1–2°). Seaward of a large trough, thick wavy stratified sediments cover the gentle slope. Cyclic loading by earthquakes is the most probable triggering mechanism for the slope instability in this area. The topmost (2–3 m) sediment is chiefly composed of hemipelagic mud with interbeds of turbidites and volcanogenic material. These sediments are highly plastic and shear resistant (over 4 kPa at the surface) in both stable and failed areas. Grain size decreases seaward, from sandy mud on the shelf to silty clay on the lower slope. Total organic matter and water contents are closely associated with sediment texture, both increasing with clay amounts from 5–10% and from 50 up to 200%, respectively.

Sedimentary characteristics and geotechnical properties of the fine-grained sediments in the South Sea were analysed on 45 sediment cores collected in part of the sea. A map of surface sediment distribution in the sea is newly presented, based on the compilation of previous localized data. Grain size of the sediment (7–9ϕ) decreases slightly but systematically with water depth, although some variations in size occur locally along the coastal area. Shear strength is substantial near the sea floor (3–5 kPa) and gradually increases downcore, indicative of slow sedimentation. Water content is largely over 100% and uniform vertically. Organic matter and CaCO 3 increase Atterberg limits of the sediment, which is highlighted in the sediment off Ulsan under the influence of coastal upwelling.

The smoothness of the interface between the insulation layer and the semiconductive conductor shields is very important to provide a uniform electrical stress gradient preserving the long term electrical performance of power cables. Any convolutions or protrusions from the semiconductive conductor shield into the insulation layer can result in localized electrical stress and induce undesired treeing or electrical degradation. An investigation of the compound melt rheology and its relationship to conductor shield convolution will be described. It will be shown that the inherent rheological properties of the semiconductive conductor shield compound in combination with the fabrication conditions in the continuous vulcanization of power cable manufacturing process determine the tendency for convolutions to develop.

New formulation technologies have been developed for application in semiconductive conductor shield compounds. These technologies offer several advantages for conductor shields relative to the traditional polyethylene copolymers of alkyl-acrylate, or vinyl-acetate, that have been in commercial use for over 30 years. New semiconductive conductor shield compounds have been tested extensively both in the laboratory and on insulated power cables. A conventional shield class of product was produced with the new technology utilizing a furnace black. It was used to manufacture a commercial scale 15 kV cable with XLPE insulation. This cable was then tested in long term wet aging under 4,4' ACLT conditions and found to exhibit excellent performance. The cable extrusion study showed excellent processability in comparison to conventional shields.

The electroluminescence test is a relatively new technique to investigate the dielectric performance of semiconductive shields and crosslinked polyethylene insulation interfaces. It is based on the electric field (voltage) at which light emission occurs as a result of charge injection and carriers recombination for a given sample geometry. A standardized sample geometry with a semicon needle-plane electrode was utilized under amplified voltage in a dry condition to monitor the electroluminescence inception voltages of crosslinked polyethylene (XLPE) and tree retardant crosslinked polyethylene insulation (TR XLPE). It resulted that EL inception voltage of TR XLPE is higher than that of XLPE. In water tree growth test, TR XLPE demonstrated to retard water tree growth under the wet aging condition.

The polymer-micelle model, formerly established by Cabane, is revised to develop a new viscosity equation to describe the dependence of dilute solution viscosity on polymer concentration in PEG/SDS aqueous solutions. Two parameters inthe new equation were proposed to characterize the influence of the polymer solution viscosity on the added surfactant. The viscosity data of polyethylene glycol (PEG) solutions containing sodium dodecyl sulfate (SDS) were measured by the Ubbelohde dilution viscometer and the new equation proved to be in good agreement with the experimental data. Copyright 2000 Academic Press.

Abstract Critically refracted seismic waves can be utilized in elucidation of physical properties of a high-impedance acoustic basement where reflection methods are not effective in general. Quality factor Q was estimated for the high-impedance acoustic basement in the continental shelf of the East Sea Korea. Various pre-processing steps for the estimation included static correction for gun delay, geometric correction data interpolation and Fourier transform. Based on the constant Q model, quality factor was computed for the upper-most layer within the basement using the spectral-ratio method. The computation gives values between 10.4 and 13.6, which fall under the range for water-saturated clastic sedimentary rock. Using seismic events refracted from the layer boundaries within the acoustic basement in the study are sedimentary layers were successfully defined. A short window AGC (automatic gain control) is an effective tool to reveal existence of the refraction boundaries. Based on a model for horizontal layers, refraction velocity and thickness were computed for each layer under a short seismic line of 3.75 km long in the continental shelf From four distinct linear events, three layers were interpreted under the water body of 150 m deep. The computed thickness is 275 m for the top layer and 200 m for the middle one. The corresponding refraction velocities are approximately 3900 m/s and 5100 m/s, respectively, The refraction event from the top of the lowest layer suggests that its phase velocity is greater than 6400 Ids. Introduction Lithology of the acoustic basement is often considered as an important factor by many industry geologists as well as academic scholars in order to elucidate geological history and formation of a sedimentary basin. For the critical angle at the top of the acoustic basement is generally very small, a conventional reflection method generally fails where the acoustic basement locates near the surface or just below the shallow water. Low primary-to-multiple ratios on reflection sections prevent from reliable geologic interpretation beneath the top surface of the basement. As a part of a marine project commenced in 1994 (Ref.1), more than 310 km of reflection data comprising four seismic lines were obtained in the East Sea of Korea through 58 seismic charnels (Fig. 1). Stacked sections over the profiles show that several depositional sequences are well defined above the acoustic basement where the water depth is deep. On the contrary, primary reflections are not evident within the basement in the continental shelf. Thai is because seismic energy can not penetrate into the acoustic basement due to a large impedance contrast between the water layer and the basement. In this work physical properties, such as seismic velocity and quality factor, of the acoustic basement are computed from critically reflected events. Geologic structures within the basement are also to be investigated based on the horizontal layer rnodel Correlation to well data or previous Seismic data is not conducted since such data are not available.

Hydrodynamic instabilities of a cylindrical plasma shell which is imploded by the pressure of an external massless fluid are considered. The plasma shell is assumed to be a compressible, isentropic fluid which is describable as an ideal gas ( p = arho/sup ..gamma../, ..gamma..not =1). The unperturbed plasma shell is assumed to undergo a self-similar motion. This assumption together with mass conservation determines the time-dependent pressure profile of the plasma shell. Linear stability analyses for this prescribed self-similar motion are carried out analytically. Stability criteria are obtained in terms of the ratio of specific heats ..gamma.. and an azimuthal mode number of perturbations. It is shown that the imploding plasma shell is unstable to compressible perturbations when ..gamma..

Heavy mineral assemblages of the sand deposit in the southeastern Yellow Sea were examined in order to reveal shelf sedimentation in the absence of significant river discharge. Hornblende dominates the mineral assemblages in most of the area, and originates from the adjacent landmass of igneous and metamorphic rocks. Sand fractions near the mud-dominant area off the southwestern coast of Korea contain the highest heavy mineral concentrations represented by stable minerals such as garnet, epidote, zircon and opaques, and are most probably derived from nearby Cretaceous sedimentary rocks. This mineral distribution, together with other known sedimentological phenomena, can be adequately explained by the shoreface retreat processes. The sand deposit thus appears to be a basal transgressive sand sheet resulting from coastal erosion during Holocene transgression.

The description and prediction of the vapor-liquid equilibrium of molecular fluid mixtures by equation of state is reviewed. Seven equations of state are compared with experimental data. Results of the comparison are reported for mixtures of non-polar and slightly polar substances over a wide image of pressure, temperature, and molecular variety. The experimental data base of the comparison includes 20 symmetric mixtures, 20 methane-containing mixtures, 17 hydrogen mixtures, 18 carbon dioxide mixtures, and 12 nitrogen mixtures. Interaction constants are determined and reported for all the mixtures studied.

A continuously variable ER (electro-rheological) damper for a passenger vehicle is proposed and its control characteristics are investigated. First, the field-dependent yield stress of arabic gum-based ER fluid is obtained using a couette type electroviscometer. The Bingham model with the yield stress is then incorporated into the governing equation of motion of the ER damper, which is derived from a bond graph model. After verifying that the damping force of the ER damper can be continuously tuned by the intensity of the electric field, a skyhook control algorithm is formulated to achieve the desired damping forces. Subsequently, control performances to track the desired damping force are evaluated through both computer simulation and experimental realization. In addition, time response characteristics of the ER damper to a high frequency control voltage are presented.

The mixing angle of ηη′ is calculated based on the symmetry breaking model. We find the mixing angle θ = 10.4 with m κ = 1200 MeV, while quadratic SU(3) mass formula gives θ = 10.3.