821 research outputs found
Thermophysical Properties of Fe-Si and Cu-Pb Melts and Their Effects on Solidification Related Processes
Among thermophysical properties, the surface/interfacial tension, viscosity, and density/molar volume of liquid alloys are the key properties for the modelling of microstructural evolution during solidification. Therefore, only reliable input data can yield accurate predictions preventing the error propagation in numerical simulations of solidification related processes. To this aim, the thermophysical properties of the Fe-Si and Cu-Pb systems were analysed and the connections with the peculiarities of their mixing behaviours are highlighted. Due to experimental difficulties related to reactivity of metallic melts at high temperatures, the measured data are often unreliable or even lacking. The application of containerless processing techniques either leads to a significant improvement of the accuracy or makes the measurement possible at all. On the other side, accurate model predicted property values could be used to compensate for the missing data; otherwise, the experimental data are useful for the validation of theoretical models. The choice of models is particularly important for the surface, transport, and structural properties of liquid alloys representing the two limiting cases of mixing, i.e., ordered and phase separating alloy systems
Wetting Behavior of Ternary Au-Ge-X (X=Sb, Sn) Alloys on Cu and Ni
Au-Ge-based alloys are potential substitutes for Pb-rich solders currently used for high-temperature applications. In the present work, the wetting behavior of two Au-Ge-X (X=Sb, Sn) ternary alloys, i.e., Au-15Ge-17Sb and Au-13.7 Ge-15.3Sn (at.%), in contact with Cu and Ni substrates has been investigated. Au-13.7Ge-15.3Sn alloy showed complete wetting on both Cu and Ni substrates. Total spreading of Au-15Ge-17Sb alloy on Cu was also observed, while the final contact angle of this alloy on Ni was about 29°. Pronounced dissolution of Cu substrates into the solder alloys investigated was detected, while the formation of Ni-Ge intermetallic compounds at the interface of both solder/Ni systems suppressed the dissolution of Ni into the solde
Effect of Applied Pmsg Dose on Reproductive Parameters for Improved Sjenica Sheep in Anestrous Season
This paper shows the results of the effects of higher dose 700 i.u. of natural gonad tropic hormone PMSG application in comparison with usual 500 i.u dose which is used at the farms during the induction and synchronization of estrus in anestrous season in Sjenica improved sheep. This experiment included 90 grown sheep divided into two groups (control group 30 sheep and experimental group 60 sheep). Both groups received polyurethane sponges impregnated with 20 mg of Fluor Geston Acetate (FGA). After 14 days both group sponges were removed. First group received 500 i.u of PMSG, usual dose, and second (experimental group) received 700 i.u of PMSG. Insemination was conducted 48-72 hours after gonad tropic hormone application. Number of sheep that lambed compared to the number of sheep that were treated was 93.33% (control) and 88.33% experimental group. Average fertility of control group sheep was 150.00% while experimental sheep had average fertility of 209.43%, which is more than 59.43% higher compared to control group. Higher dose of PMSG led to higher number of triplets by 7.34%, quadruplets by 14.41% and quintuplets by 4.50% in the experimental group. Higher dose by 200 i.u of PMSG had a positive effect and increased fertility by 59.43%, which negates zero hypothesis that there is no difference between researched treatments and it proved hypothesis that higher dose of PMSG has a positive effect on Sjenica improved sheep during anestrous season
Layer Attitude and Thickness Measurements of the Three Interior Layered Deposits Mounds within Juventae Chasma, Mars
Wetting and Soldering Behavior of Eutectic Au-Ge Alloy on Cu and Ni Substrates
Au-Ge-based alloys are interesting as novel high-temperature lead-free solders because of their low melting point, good thermal and electrical conductivity, and high corrosion resistance. In the present work, the wetting and soldering behavior of the eutectic Au-28Ge (at.%) alloy on Cu and Ni substrates have been investigated. Good wetting on both substrates with final contact angles of 13° to 14° was observed. In addition, solder joints with bond shear strength of 30MPa to 35MPa could be produced under controlled conditions. Cu substrates exhibit pronounced dissolution into the Au-Ge filler metal. On Ni substrates, the NiGe intermetallic compound was formed at the filler/substrate interface, which prevents dissolution of Ni into the solder. Using thin filler metal foils (25μm), complete consumption of Ge in the reaction at the Ni interface was observed, leading to the formation of an almost pure Au layer in the soldering zon
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The Cellular and Physiological Basis for Lung Repair and Regeneration: Past, Present, and Future.
The respiratory system, which includes the trachea, airways, and distal alveoli, is a complex multi-cellular organ that intimately links with the cardiovascular system to accomplish gas exchange. In this review and as members of the NIH/NHLBI-supported Progenitor Cell Translational Consortium, we discuss key aspects of lung repair and regeneration. We focus on the cellular compositions within functional niches, cell-cell signaling in homeostatic health, the responses to injury, and new methods to study lung repair and regeneration. We also provide future directions for an improved understanding of the cell biology of the respiratory system, as well as new therapeutic avenues
Cost Optimization of Ice Distribution
Two questions regarding minimizing fuel costs while delivering ice along a pre-set route are tackled.
The first question is when demand exceeds the load of a single truck, so that a second truck of ice has to be taken to some point of the route for the driver/salesman to continue with that for the rest of the route: Is it better:
1) for the first truck to deliver starting from the costumer nearest to the base, or
2) for the first truck to start the delivery from the last costumer (the most distant from the base)?
We show that the second strategy was better for the particular data looked at, and we have the basis of an algorithm for deciding which strategy is the better for a given delivery schedule.
The second question concerns how best to modify a regular sales route when an extra delivery has to be made. Again, the basis for an algorithm to decide how to minimize fuel costs is derived
The effects of maternal anxiety during pregnancy on IGF2/H19 methylation in cord blood
Compelling evidence suggests that maternal mental health in pregnancy can influence fetal development. The imprinted genes, insulin-like growth factor 2 (IGF2) and H19, are involved in fetal growth and each is regulated by DNA methylation. This study aimed to determine the association between maternal mental well-being during pregnancy and differentially methylated regions (DMRs) of IGF2 (DMR0) and the IGF2/H19 imprinting control region (ICR) in newborn offspring. Maternal depression, anxiety and perceived stress were assessed at 28 weeks of pregnancy in the Barwon Infant Study (n = 576). DNA methylation was measured in purified cord blood mononuclear cells using the Sequenom MassArray Platform. Maternal anxiety was associated with a decrease in average ICR methylation (Delta = -2.23%;95% CI = -3.68 to -0.77%), and across all six of the individual CpG units in anxious compared with non-anxious groups. Birth weight and sex modified the association between prenatal anxiety and infant methylation. When stratified into lower ( 3530 g) birth weight groups using the median birth weight, there was a stronger association between anxiety and ICR methylation in the lower birth weight group (Delta = -3.89%;95% CI = -6.06 to -1.72%), with no association in the higher birth weight group. When stratified by infant sex, there was a stronger association in female infants (Delta = -3.70%;95% CI = -5.90 to -1.51%) and no association in males. All the linear regression models were adjusted for maternal age, smoking and folate intake. These findings show that maternal anxiety in pregnancy is associated with decreased IGF2/H19 ICR DNA methylation in progeny at birth, particularly in female, low birth weight neonates. ICR methylation may help link poor maternal mental health and adverse birth outcomes, but further investigation is needed
Mechanistic Oral Absorption Modeling and Simulation for Formulation Development and Bioequivalence Evaluation: Report of an FDA Public Workshop
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138394/1/psp412204.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138394/2/psp412204_am.pd
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