Melter feed tank operating map from the FA-10.02 test data

The operability of the Melter Feed Tank (MFT) feed loops has been tested during the DWPF-FA-10.02 test. The ability to feed the melter at three distinct melter feed rates (0.20, 0.45, and 0.90 gpm), two distinct agitator speeds (65 and 130 rpm), varying liquid levels, and varying slurry rheologies was tested. This report correlates the operability of the feed loops with the above mentioned variables. The data are presented in the form of operating maps, Figs. 1 through 4, which are plots of the liquid level versus the wt% total solids (and yield stress) for two agitator speeds. The maps are divided into regions of acceptable feed loop operation and unacceptable feed loop operation. This report does not consider how closely the compositions of the MFT, the melter feed lines, and the Hydragard samples agree. The significant observations in this report are as follows: Both feed loops satisfy the operability criteria down to a liquid level below the upper impeller blade at low speed agitation (65 rpm). Under high speed agitation (130 rpm), feed loop No. 2 operates much more poorly than feed loop No. 1. The uncertainty associated with the wt% total solids of a slurry sample is larger than the current design basis range for total solids. The dilution of slurry due to pump priming is shown graphically in the chronological presentation of wt% total solids

Refrigerants with Low Environmental Impact for Refrigeration Applications

New refrigerants with considerable low environmental impact are currently under evaluation by the refrigeration industry. Such refrigerants could be used in place of high global warming fluids like R404A. Among these new fluids are 1234ze, N-13, L-40 and N-40. Initial laboratory evaluations of these refrigerants showed good energy efficiency due to their good thermal properties. These initial evaluations were followed by larger scale (field) trials, refrigerant–oil property measurements, and also material compatibility. This study presents and discusses results of such evaluations, and extends the assessment to LCCP using different refrigeration technologies and refrigerants

Nature and origin of mineral coatings on volcanic rocks of the Black Mountain, Stonewall Mountain and Kane Springs Wash volcanic centers, southern Nevada

Surface coatings on volcanic rock assemblages that occur at select tertiary volcanic centers in southern Nevada were investigated using LANDSAT 5 Thematic Mapper imagery. Three project sites comprise the subject of this study: the Kane Springs Wash, Black Mountain, and Stonewall Mountain volcanic centers. LANDSAT 5 TM work scenes selected for each area are outlined along with local area geology. The nature and composition of surface coatings on the rock types within the subproject areas are determined, along with the origin of the coatings and their genetic link to host rocks, geologic interpretations are related to remote sensing units discriminated on TM imagery. Image processing was done using an ESL VAX/IDIMS image processing system, field sampling, and observation. Aerial photographs were acquired to facilitate location on the ground and to aid stratigraphic differentiation

Using milk flow rate to investigate milk ejection in the left and right breasts during simultaneous breast expression in women

<p>Abstract</p> <p>Background</p> <p>Milk ejection is essential for a successful lactation, however techniques to measure milk ejection in women are often complex and invasive. Recent research has demonstrated that at milk ejection, milk duct diameter increased in the breast (measured by ultrasound) at the same time as milk flow rate increased (measured using a weigh balance). This study aimed to evaluate a purpose-built continuous weigh balance (Showmilk, Medela AG) to measure changes in milk flow rate from the breast to identify milk ejections during milk expression. In addition, the Showmilk was used to determine if milk ejection occurred simultaneously in both breasts during double pumping.</p> <p>Methods</p> <p>Increased milk flow rates during single pumping were compared to simultaneous ultrasound measurements of increased milk duct diameters in 14 mothers. In addition, increases in milk flow rate were compared between the left and right breasts of 28 mothers during double pumping for 15 minutes with two separate electric breast pumps attached to two Showmilks to record milk flow rate.</p> <p>Results</p> <p>Increased milk flow rates were associated with increased milk duct diameters during single pumping. The mean number of milk ejections was not different between the Showmilk (4.2 ± 2.0) and ultrasound (4.5 ± 1.5) techniques. Overall, 67 milk ejections were measured and of these, 48 (72%) were identified by both techniques. The left and right breasts responded synchronously with 95.5% of the flow rate increases corresponding between the breasts. The mean number of milk ejections identified by an increase in milk flow rate during double pumping was 5.1 ± 1.7 and 5.0 ± 1.7 for the left and right breasts, respectively. In addition, mothers chose the same expression vacuum for the left (-198 ± 31 mmHg) and right (193 ± 33 mmHg) breasts.</p> <p>Conclusion</p> <p>The Showmilk can simply and non-invasively record milk ejections by measuring increases in milk flow rate that correspond with increases in milk duct diameter. For the first time measurement of milk flow rate has been used to confirm that milk ejections occur simultaneously in the left and right breasts during double pumping. The use of the Showmilk will facilitate further research into the relationship of milk ejection and milk removal.</p

Integrin α_IIbβ₃ activation and clustering in minimal synthetic cells

Platelet adhesion and activation are mediated by integrin αIIbβ3 clustering, which is crucial for the hemostatic function of platelets. In an activated state, integrins provide the connection between the extracellular matrix and the actin cytoskeleton through a variety of cytoplasmic proteins, such as talin. Here, droplet-based microfluidics is applied to generate cell-sized giant unilamellar vesicles (GUVs) with a defined molecular composition to quantify the adhesion of integrin αIIbβ3-containing protocells in relation to the number of integrin–talin head domain (THD) complexes. Furthermore, it is shown that THD induces integrin clustering in protocells adhering to fibrinogen. The formation of this molecular link, which has, so far, only been observed in vivo, is an essential step in synthetic cell design to recapitulate integrin-mediated bidirectional signaling across the membrane. These results pave the way for further quantitative investigations of protein–protein interactions between integrins and associated proteins and their assembly within such defined, but complex, synthetic cells. An essential future step to mimic the complex interaction between cells and their environment will be to combine synthetic approaches with peptide chemistry to guide the molecular mechanisms involved in integrin binding and activation

Combined Effects of Botulinum Toxin Injection and Hind Limb Unloading on Bone and Muscle

Bone receives mechanical stimulation from two primary sources, muscle contractions and external gravitational loading; but the relative contribution of each source to skeletal health is not fully understood. Understanding the most effective loading for maintaining bone health has important clinical implications for prescribing physical activity for the treatment or prevention of osteoporosis. Therefore, we investigated the relative effects of muscle paralysis and reduced gravitational loading on changes in muscle mass, bone mineral density, and microarchitecture. Adult female C57Bl/6J mice (n = 10/group) underwent one of the following: unilateral botulinum toxin (BTX) injection of the hind limb, hind limb unloading (HLU), both unilateral BTX injection and HLU, or no intervention. BTX and HLU each led to significant muscle and bone loss. The effect of BTX was diminished when combined with HLU, though generally the leg that received the combined intervention (HLU+BTX) had the most detrimental changes in bone and muscle. We found an indirect effect of BTX affecting the uninjected (contralateral) leg that led to significant decreases in bone mineral density and deficits in muscle mass and bone architecture relative to the untreated controls; the magnitude of this indirect BTX effect was comparable to the direct effect of BTX treatment and HLU. Thus, while it was difficult to definitively conclude whether muscle force or external gravitational loading contributes more to bone maintenance, it appears that BTX-induced muscle paralysis is more detrimental to muscle and bone than HLU.National Institutes of Health (U.S.) (H R21 AR057522)United States. National Aeronautics and Space Administration (NNX10AE39G)National Space Biomedical Research Institute (NASA NCC 9-58)United States. National Aeronautics and Space Administration (NASA-Jenkins predoctoral fellowship)Northrop Grumman Corporation (Aerospace Systems PhD Training Fellowship

Palladium nanoparticles by electrospinning from poly(acrylonitrile-co-acrylic acid)-PdCl2 solutions. Relations between preparation conditions, particle size, and catalytic activity

Catalytic palladium (Pd) nanoparticles on electrospun copolymers of acrylonitrile and acrylic acid (PAN-AA) mats were produced via reduction of PdCl2 with hydrazine. Fiber mats were electrospun from homogeneous solutions of PAN-AA and PdCl2 in dimethylformamide (DMF). Pd cations were reduced to Pd metals when fiber mats were treated in an aqueous hydrazine solution at room temperature. Pd atoms nucleate and form small crystallites whose sizes were estimated from the peak broadening of X-ray diffraction peaks. Two to four crystallites adhere together and form agglomerates. Agglomerate sizes and fiber diameters were determined by scanning and transmission electron microscopy. Spherical Pd nanoparticles were dispersed homogeneously on the electrospun nanofibers. The effects of copolymer composition and amount of PdCl2 on particle size were investigated. Pd particle size mainly depends on the amount of acrylic acid functional groups and PdCl2 concentration in the spinning solution. Increasing acrylic acid concentration on polymer chains leads to larger Pd nanoparticles. In addition, Pd particle size becomes larger with increasing PdCl2 concentration in the spinning solution. Hence, it is possible to tune the number density and the size of metal nanoparticles. The catalytic activity of the Pd nanoparticles in electrospun mats was determined by selective hydrogenation of dehydrolinalool (3,7-dimethyloct-6- ene-1-yne-3-ol, DHL) in toluene at 90 °C. Electrospun fibers with Pd particles have 4.5 times higher catalytic activity than the current Pd/Al2O3 catalyst

A phylogenomic analysis of Marek's disease virus reveals independent paths to virulence in Eurasia and North America

Virulence determines the impact a pathogen has on the fitness of its host, yet current understanding of the evolutionary origins and causes of virulence of many pathogens is surprisingly incomplete. Here, we explore the evolution of Marek's disease virus (MDV), a herpesvirus commonly afflicting chickens and rarely other avian species. The history of MDV in the 20th century represents an important case study in the evolution of virulence. The severity of MDV infection in chickens has been rising steadily since the adoption of intensive farming techniques and vaccination programs in the 1950s and 1970s, respectively. It has remained uncertain, however, which of these factors is causally more responsible for the observed increase in virulence of circulating viruses. We conducted a phylogenomic study to understand the evolution of MDV in the context of dramatic changes to poultry farming and disease control. Our analysis reveals evidence of geographical structuring of MDV strains, with reconstructions supporting the emergence of virulent viruses independently in North America and Eurasia. Of note, the emergence of virulent viruses appears to coincide approximately with the introduction of comprehensive vaccination on both continents. The time-dated phylogeny also indicated that MDV has a mean evolutionary rate of ~1.6 × 10−5 substitutions per site per year. An examination of gene-linked mutations did not identify a strong association between mutational variation and virulence phenotypes, indicating that MDV may evolve readily and rapidly under strong selective pressures and that multiple genotypic pathways may underlie virulence adaptation in MDV

Sampling Local Fungal Diversity in an Undergraduate Laboratory using DNA Barcoding

Traditional methods for fungal species identification require diagnostic morphological characters and are often limited by the availability of fresh fruiting bodies and local identification resources. DNA barcoding offers an additional method of species identification and is rapidly developing as a critical tool in fungal taxonomy. As an exercise in an undergraduate biology course, we identified 9 specimens collected from the Hendrix College campus in Conway, Arkansas, USA to the genus or species level using morphology. We report that DNA barcoding targeting the internal transcribed spacer (ITS) region supported several of our taxonomic determinations and we were able to contribute 5 ITS sequences to GenBank that were supported by vouchered collection information. We suggest that small-scale barcoding projects are possible and that they have value for documenting fungal diversity