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At GE Research, we are combining “physics” with artificial intelligence and machine learning to advance manufacturing design, processing, and inspection, turning innovative technologies into real products and solutions across our industrial portfolio. This article provides a snapshot of how this physical plus digital transformation is evolving at GE.
Air pollution is a persistent and well-established public health problem in India: emissions from coal-fired power plants have been associated with over 80,000 premature deaths in 2015. Premature deaths could rise by four to five times this number by 2050 without additional pollution controls. We site a model 500 MW coal-fired electricity generating unit at eight locations in India and examine the benefits and costs of retrofitting the plant with a flue-gas desulfurization unit to reduce sulfur dioxide emissions. We quantify the mortality benefits associated with the reduction in sulfates (fine particles) and value these benefits using estimates of the value per statistical life transferred to India from high income countries. The net benefits of scrubbing vary widely by location, reflecting differences in the size of the exposed population. They are highest at locations in the densely populated north of India, which are also among the poorest states in the country.
Fertilization in higher plants induces many structural and physiological changes in the fertilized egg, and represents the transition from the haploid female gamete to the diploid zygote, the first cell of a sporophyte. Some changes are induced extremely rapidly following fusion with sperm cells and are the preclusions of egg activation. This review focuses on the early changes that occur in the egg after fusion with sperm cells, but before nuclear fusion. Reported changes include cell shrinkage, cell wall formation, polarity change, oscillation in Ca2+ concentration, and DNA synthesis. In addition, the current understanding of egg activation is summarized and the possible functional relevance of the changes is explored.
The aim of this study was to investigate the in vivo degradation mechanism and the mechanical properties of poly(lactide-co-glycolide)/beta-tricalcium phosphate (PLGA/β-TCP) composite anchors. Anchors composed of PLGA and β-TCP were implanted in the dorsal subcutaneous tissue of beagle dogs for 6, 12, 16, and 26 weeks. The degradation of the materials was evaluated by measuring the changes in thermal behavior, crystallinity, and mechanical properties. Scanning electron microscope (SEM) was used to observe the surface and longitudinal section of the material. The evaluation of mechanical strength retention and degradation properties suggest that the addition of β-TCP particles efficiently enhances their mechanical properties and thermal characteristics and delays their degradation rate. By analyzing the results of SEM, X-ray diffraction, and differential scanning calorimetry, we can infer that after 12 weeks, the connection between β-TCP and PLGA becomes less compact, which accelerates the decline of mechanical strength.
Combining density functional theory calculations and temperature programmed desorption (TPD) experiments, the adsorption behavior of various sulfur containing compounds, including C2H5SH, CH3SCH3, tetrahydrothiophene, thiophene, benzothiophene, dibenzothiophene, and their derivatives on the coordinately unsaturated sites of Mo27Sx model nanoparticles, are studied systematically. Sulfur molecules with aromaticity prefer flat adsorption than perpendicular adsorption. The adsorption of nonaromatic molecules is stronger than the perpendicular adsorption of aromatic molecules, but weaker than the flat adsorption of them. With gradual hydrogenation (HYD), the binding affinity in the perpendicular adsorption modes increases, while in flat adsorption modes it increases first, then decreases. Significant steric effects on the adsorption of dimethyldibenzothiophene were revealed in perpendicular adsorption modes. The steric effect, besides weakening adsorption, could also activate the S–C bonds through a compensation effect. Finally, by comparing the theoretical adsorption energies with the TPD results, we suggest that HYD and direct-desulfurization path may happen simultaneously, but on different active sites.
A high power laser system was used to drive the ignition of inertial confinement fusion (ICF), of which the high energy, the uniform focal spot, the accurate laser waveform, and the synchronization between the laser beams are key parameters. To accomplish this, global laser characteristics control should be assured, which was the main purpose of the injection laser system. In this paper, the key technological progress involved in the improvement of the performance of the injection laser of SG-II is reported, including frequency domain control, time domain control, near-field spatial shaping, pre-amplifier technology, and the optical parametric chirped pulse amplification pump source.
Solving the problem of ship weather routing has been always a goal of nautical navigation research and has been investigated by many scientists. The operation schedule of an oceangoing ship can be influenced by wave or wind disturbances, which complicate route planning. In this paper, we present a real-coded genetic algorithm to determine the minimum voyage route time for point-to-point problems in a dynamic environment. A fitness assignment method based on an individual's position in the sorted population is presented, which greatly simplifies the calculation of fitness value. A hybrid mutation operator is proposed to enhance the search for the optimal solution and maintain population diversity. Multi-population techniques and an elite retention strategy are employed to increase population diversity and accelerate convergence rates. The effectiveness of the algorithm is demonstrated by numerical simulation experiments.
Universal salt iodisation (USI) has been successfully implemented in China for more than 15 years. Recent evidence suggests that the definition of ‘adequate iodine’ (100–199 µg/l) be revised to ‘sufficient iodine’ (100–299 µg/l) based on the median urinary iodine concentration (MUI) in school-age children. The objective of this study was to determine the prevalence of thyroid dysfunction in populations after long-term salt iodisation and examine whether the definition of adequate iodine can be broadened to sufficient iodine based on the thyroid function in four population groups. A cross-sectional survey was conducted in six provinces in the northern, central and southern regions of China. Four population groups consisting of 657 children, 755 adults, 347 pregnant women and 348 lactating women were recruited. Three spot urinary samples were collected over a 10-d period and blood samples were collected on the 1st day. In the study, among the adults, pregnant women and lactating women, the prevalence rates of elevated thyroglobulin antibody and thyroid microsomal antibody levels were 12·4, 8·5 and 7·8 %, and 12·1, 9·1 and 9·1 %, respectively. Abnormally high thyroid dysfunction prevalence was not observed after more than 15 years of USI in China because the thyroid dysfunction rates were all <5 %. The recommended range should be cautiously broadened from adequate iodine to sufficient iodine according to the MUI of school-age children considering the high levels of hormones and antibodies in the other populations. Adults, particularly pregnant women positive for thyroid antibodies, should be closely monitored.
This paper reports the measurement of the energy loss of protons at the energy of 100 keV penetrating a partially ionized hydrogen plasma. The plasma of ne ≈ 1015–16 cm−3; Te ≈ 1–2 eV and lifetime of about 8 µs is created by the hydrogen gas discharge. The experimental results show an increase of a factor of 2.8 in the energy loss, which are in good agreement with the Bethe, Standard Stopping Model, Li–Petrasso and Vlasov models’ predictions within the error limit. The Bethe–Bloch Coulomb logarithm term is found to increase by a factor of 4.0 for free electrons as compared with the situation where bound electrons prevail. The potential application of protons energy loss for diagnosing the electron density in plasma is proposed too.
Dome A is the highest ice feature in Antarctica, at over 4000 m a.s.l., and overlies the Gamburtsev mountains. It is believed that deep ice-core drilling in this area may reveal the oldest ice in Antarctica, providing an unparalleled paleoclimate record in excess of 1 Ma, and perhaps going back as far as 1.2 Ma (Xiao and others, 2008). However, little is known about this area because its height and distance from the coast and scientific stations makes access difficult.
Thermal stability up to 400 °C of nanocrystalline (NC) Ni electrodeposits (EDs) with a mean grain size of 28 nm and dispersions of a small amount of CeO2 nanoparticles has been investigated by comparing with two CeO2-free NC Ni counterparts, one with a slightly smaller mean grain size of 18 nm and the other with a slightly larger mean grain size of 34 nm. The results show that the co-deposition of CeO2 particles has dual effects on the thermal stability of the NC Ni EDs, i.e., it promotes the grain growth at the beginning but retards subsequently. It is proposed that the CeO2 co-deposition leads to a decrease in sulfur level and an increase in the plane defects as a result of introduction of incoherent Ni/CeO2 interfaces, which play dominant roles in the grain growth at low temperatures; while the drag effect of CeO2 dispersions becomes dominant at higher temperatures.
The push–pull fatigue characteristics of the peak-aged Mg–0.2Zn–0.5Zr alloys with different addition levels of neodymium (Nd) have been investigated. The fatigue strength (σf) of the Mg–xNd–0.2Zn–0.5Zr (NZx0K) alloy increases proportionally with the increase of the Nd content (CNd) as follows: σf (T6) ≈ (13.8–14.0) CNd + 46 (for x between 0 and 3.0 wt%). The cyclic stress amplitude also increases but the plastic strain value decreases with the increase of the Nd content. The studied alloys exhibit the strain hardening followed by cyclic softening during fatigue test. During the low-cycle fatigue (LCF) test, the cracks originate from the cyclic deformation and cumulative damage. In high-cycle fatigue (HCF), the failure is due to the cyclic deformation and damage irreversibly caused by environment-assisted cyclic slip. The LCF lives of the alloys fitted well with the Coffin–Manson relation and Basquin laws, the three-parameter equation, and the energy-based concepts. The developed multi-scale fatigue (MSF) life models can be used to predict the LCF and HCF lives of the alloys. Among these models, the MSF life can well capture the influence of Nd addition on fatigue.
Hydrogenated amorphous carbon (a-C:H) films with a designed buffer layer of amorphous hydrogenated silicon carbide on the substrates were fabricated by plasma enhanced chemical vapor deposition (PECVD). The effect of radio frequency (RF) power on the structural and optical properties of a-C:H films was investigated. The ratios of sp3 to sp2 of carbon atoms and hydrogen contents in the RF power range of 75–175 W are determined and a similar trend as a function of power. The increase of sp3 to sp2 ratio leads to the increase of transmittance and optical gap of a-C:H films. a-C:H film under an RF power of 175 W possesses high transmissive ability (>80%) in the visible wave length, even the highest transmittance value of about 94.2% is achieved at the wave length 550 nm. These results show the optimal a-C:H films which are promising for the applications in the area of solar cells acting a window layer and antireflection layer.
X-ray powder diffraction (XRPD) data for Palbociclib, C24H29N7O2, are reported [a = 18.182(2) Å, b = 11.508(1) Å, c = 5.041(1) Å, α = 81.282(7)°, β = 97.423(7)°, γ = 102.415(2)°, unit-cell volume V = 1013.1(4) Å3, Z = 2, and space group P-1. All XRPD measured lines were indexed and no detectable impurities were observed.
Bullying is a common problem in school. Engagement in bullying has been known to have many adverse effects, even including suicide. Examining which factor will moderate or mediate the pathway from victimisation to suicidal ideation is needed to develop effective intervention initiatives. This study aimed to examine the mediator and moderator roles of perceived social support in the relationship between victimisation and suicidal ideation. The participants in the study were 946 Chinese adolescents (402 girls, 544 boys) who ranged in age from 11 to 16 years old. The results showed that 48.1% of these adolescents reported being bullied in school. Victimisation was positively correlated with suicidal ideation. There was evidence that perceived social support buffered, as well as partially mediated, the relationship between victimisation and suicidal ideation. Results suggest that helping students to seek more support from their parents and peers may be an effective bullying intervention program.
Homogeneous equilibrium model (HEM) has been widely used in cavitating flow simulations. The major feature of this model is that a single equation of state (EOS) is proposed to describe the thermal behavior of bubbly liquid, where both kinematic and thermal equilibrium is assumed between two phases. In this paper, the HEM was coupled with multi-relaxation-time lattice Boltzmann model (MRT-LBM) and the acoustic behavior was simulated. Two approaches were applied alternatively: adjusting speed of sound (Buick, J. Phys. A, 2006, 39:13807-13815) and setting real gas EOS. Both approaches result in high accuracy in acoustic speed predictions for different void (gas) volume of fractions. It is demonstrated that LBM could be successfully applied as a Navier-Stokes equation solver for industrial applications. However, further dissipation and dispersion analysis shows that Shan-Chen type approaches of LBM are deficient, especially in large wave-number region.
Schistosoma japonicum, a human blood fluke, causes a parasitic disease affecting millions of people in Asia. Thioredoxin–glutathione system of S. japonicum plays a critical role in maintaining the redox balance in parasite, which is a potential target for development of novel antischistosomal agents. Here we cloned the gene of S. japonicum thioredoxin (SjTrx), expressed and purified the recombinant SjTrx in Escherichia coli. Functional assay shows that SjTrx catalyses the dithiothreitol (DTT) reduction of insulin disulphide bonds. The coupling assay of SjTrx with its endogenous reductase, thioredoxin glutathione reductase from S. japonicum (SjTGR), supports its biological function to maintain the redox homeostasis in the cell. Furthermore, the crystal structure of SjTrx in the oxidized state was determined at 2·0 Å resolution, revealing a typical architecture of thioredoxin fold. The structural information of SjTrx provides us important clues for understanding the maintenance function of redox homeostasis in S. japonicum and pathogenesis of this chronic disease.
The carburizing behaviors and mechanisms for Cr35Ni45Nb alloy subjected to different service conditions were studied in a high-temperature vacuum environment. Generally, the carburizing process of an alloy is always accompanied by diffusional heterogeneous reactions regardless of the service condition of the alloy. For a carburized original tube, there is a layered structure at the inner wall of the tube, which is comprised of a M7C3 zone, a M7C3–M23C6 mixed zone, and a M23C6 zone with different morphologies. However, for a 6-year tube (short for a tube serviced for 6 years), the composite oxide layers formed previously act as effective barriers to carbon infiltration. Moreover, the Cr2O3 scale tended to be carbonized to form carbide scale to spall from the surface in a reducing environment, while the SiO2 kept stable all along. Once the oxide layers were removed or carbonized enough, inconceivable internal carburization occurred widely.