5,267 research outputs found

    The changes in chemical composition during development of the bovine nuchal ligament

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    Whole bovine nuchal ligaments, or portions thereof (in the case of commercially valuable animals), were obtained from 45 animals (28 fetal and 17 postnatal) ranging in age from 110 days of gestation to 10 yr. Insoluble elastin was quantitatively prepared from the fresh ligaments by extraction with hot alkali and by a combination of multiple extractions with alkaline buffer and then repeated autoclaving. When adult samples were examined, the yields of insoluble residue by these two methods were very similar, but with young fetal samples the second method gave significantly higher values, because of incomplete purification of the elastin residue. The changes in the concentration of collagen, alkali-insoluble elastin, and DNA have been examined. DNA concentration, and, thus, cell population density, fell progressively during the fetal period of development, to reach a steady value soon after birth. Collagen appeared in appreciable quantities before elastin, but its concentration was rapidly halved at about the time of birth. Insoluble elastin concentration was low until the end of the 7th fetal month, at which time it began to rise rapidly. The rate of increase in elastin concentration remained high throughout the next 10–12 wk, by which time the adult value had been reached. Quantitative studies, on the basis of the whole ligament, showed that the total cell content rises to a maximum at birth, but falls soon after to a level about half that at birth. Total collagen production and elastin deposition continue at a steady, maximal rate over the interval from 235 days of gestation to the end of the 1st postnatal month. It is concluded that the immediate postnatal period would be the most favorable phase in which to attempt the isolation of the soluble precursor elastin

    Aerial applications dispersal systems control requirements study

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    Performance deficiencies in aerial liquid and dry dispersal systems are identified. Five control system concepts are explored: (1) end of field on/off control; (2) manual control of particle size and application rate from the aircraft; (3) manual control of deposit rate on the field; (4) automatic alarm and shut-off control; and (5) fully automatic control. Operational aspects of the concepts and specifications for improved control configurations are discussed in detail. A research plan to provide the technology needed to develop the proposed improvements is presented along with a flight program to verify the benefits achieved

    Teaching Care Homes : leading and facilitating cross-sector collaborations : A Care England Programme in partnership with the Foundation of Nursing Studies and the Burdett Trust for Nursing : application pack

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    Background Information about the Programme During 2016/17, Care England, with funding from the Department of Health, co-ordinated an exciting pilot programme to explore and develop the concept of Teaching Care Homes i.e. centres of excellence in person-centred care where learning and innovation is a continuous process (see: http://www.careengland.org.uk/teaching-care-home-pilot). These centres of excellence are acknowledged as supportive places for staff to work, where they feel valued and confident to take responsibility for care and innovation. The homes offer a positive and meaningful learning environment for students and staff. Most importantly, residents and families experience effective, compassionate and safe care that is centred on their needs. The pilot has realised a number of key outcomes including improvements in care and services and increased commitment to learning for all. It has also raised the profile of long-term care as a career choice that is exciting, challenging, rewarding and forward thinking. This is a vital part of addressing the issues of recruitment and retention of registered nursing and other care workforce, which has significant cost saving implications. Using the learning from the pilot programme, Care England was successful in securing continued funding from the Burdett Trust for Nursing to spread and extend Teaching Care Homes across England. Over a two-year period, and in partnership with the Foundation of Nursing Studies (FoNS), this programme will support the development of a further ten homes (five home in 2018/19 and a further five homes in 2019/20). Working together, the five homes engaged in the programme during 2018/2019 decided to explore and develop activity around three interlinked priority areas: inspiring others, cross-sector and interprofessional working, and intergenerational working and engagement. They are working creatively within their homes, but also with partners in the community, education and health to enhance care experiences and learning and development opportunities (see: https://www.fons.org/programmes/teaching-care-homes). This activity is exemplifying the ways in which nurse-led care home teams can be leaders and facilitators of exciting innovations. With this in mind, moving into the second year of the partnership with the Burdett Trust for Nursing, Care England and FoNS want to offer five nurse-led care home teams the opportunity to lead and facilitate a tangible and realistic cross-sector collaboration that will enhance care experiences and outcomes and/or learning and development opportunities. The programme is only open to care homes in England

    Observations of free–free and anomalous microwave emission from LDN 1622 with the 100 m Green Bank Telescope

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    LDN 1622 has previously been identified as a possible strong source of dust-correlated anomalous microwave emission (AME). Previous observations were limited by resolution meaning that the radio emission could not be compared with current generation high-resolution infrared data from Herschel, Spitzer or Wide-field Infrared Sky Explorer. This paper presents arcminute resolution mapping observations of LDN 1622 at 4.85 and 13.7 GHz using the 100 m Robert C. Byrd Green Bank Telescope. The 4.85 GHz map reveals a corona of free–free emission enclosing LDN 1622 that traces the photodissociation region of the cloud. The brightest peaks of the 4.85 GHz map are found to be within ≈10 per cent agreement with the expected free–free predicted by Southern H-Alpha Sky Survey Atlas H α data of LDN 1622. At 13.7 GHz, the AME flux density was found to be 7.0 ± 1.4 mJy and evidence is presented for a rising spectrum between 13.7 and 31 GHz. The spinning dust model of AME is found to naturally account for the flux seen at 13.7 GHz. Correlations between the diffuse 13.7 GHz emission and the diffuse mid-infrared emission are used to further demonstrate that the emission originating from LDN 1622 at 13.7 GHz is described by the spinning dust model

    First Season QUIET Observations: Measurements of Cosmic Microwave Background Polarization Power Spectra at 43 GHz in the Multipole Range 25 ≤ ℓ ≤ 475

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    The Q/U Imaging ExperimenT (QUIET) employs coherent receivers at 43 GHz and 94 GHz, operating on the Chajnantor plateau in the Atacama Desert in Chile, to measure the anisotropy in the polarization of the cosmic microwave background (CMB). QUIET primarily targets the B modes from primordial gravitational waves. The combination of these frequencies gives sensitivity to foreground contributions from diffuse Galactic synchrotron radiation. Between 2008 October and 2010 December, over 10,000 hr of data were collected, first with the 19 element 43 GHz array (3458 hr) and then with the 90 element 94 GHz array. Each array observes the same four fields, selected for low foregrounds, together covering ≈1000 deg^2. This paper reports initial results from the 43 GHz receiver, which has an array sensitivity to CMB fluctuations of 69 μK√s. The data were extensively studied with a large suite of null tests before the power spectra, determined with two independent pipelines, were examined. Analysis choices, including data selection, were modified until the null tests passed. Cross-correlating maps with different telescope pointings is used to eliminate a bias. This paper reports the EE, BB, and EB power spectra in the multipole range ℓ = 25-475. With the exception of the lowest multipole bin for one of the fields, where a polarized foreground, consistent with Galactic synchrotron radiation, is detected with 3σ significance, the E-mode spectrum is consistent with the ΛCDM model, confirming the only previous detection of the first acoustic peak. The B-mode spectrum is consistent with zero, leading to a measurement of the tensor-to-scalar ratio of r = 0.35^(+1.06)_(–0.87). The combination of a new time-stream "double-demodulation" technique, side-fed Dragonian optics, natural sky rotation, and frequent boresight rotation leads to the lowest level of systematic contamination in the B-mode power so far reported, below the level of r = 0.1

    A single amino acid exchange transfers VP16-induced positive control from the Oct-1 to the Oct-2 homeo domain

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    The selective association of the herpesvirus trans-activator VP16 with the human Oct-1 homeo domain is a model for differential positive transcriptional control by homeo domains. VP16 discriminates between the closely related homeo domains of Oct-1 and Oct-2 by distinguishing among their seven amino-acid differences; these differences lie on the surface that is thought to be accessible when the homeo domain is bound to DNA. Only two of these seven differences are recognized by VP16, one in each of the first two alpha-helices of the tri-alpha-helical homeo domain. The major determinant for selective association with VP16 in vitro and VP16-induced positive control in vivo is a single glutamic acid residue at position 22 in the first alpha-helix of the Oct-1 homeo domain, but the acidic properties of this residue are not critical for association with VP16 in vitro or in vivo, because it can be replaced by glutamine with little or no deleterious effect. Mere replacement of the single corresponding alanine residue in the Oct-2 homeo domain with the key glutamic acid residue is sufficient to confer on the Oct-2 homeo domain the ability to associate with VP16 in vitro and respond to VP16-induced positive control in vivo. Thus, the specificity of homeo domain positive control can be conferred by a single amino acid difference

    Coherent Arrays for Astronomy and Remote Sensing - Final Report

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    The Coherent Arrays for Astronomy and Remote Sensing Program sponsored by the Keck Institute for Space Studies has had a profound impact on astronomy at Caltech – both at JPL and on campus – and worldwide. It provided funds for the establishment of a world-class coherent detector laboratory – the Cahill Radio Astronomy Laboratory (CRAL) that, in collaboration with JPL and Northrop Grumman, now sets the global standard in coherent detectors in the centimeter-millimeter wavelength range – as shown by three key highlights: (i) NRAO’s recent selection of CRAL MMIC detectors over its own in house MIC detectors for the upgrade of the ALMA Band 2 receivers; (ii) NSF’s funding of a 16-element 85 GHz – 115 GHz focal plane array (ARGUS) for the Green Bank Telescope (1M);and(iii)NSF’sfundingofthe26GHz–34GHzCOMappingArrayPathfinder(COMAP1M); and (iii) NSF’s funding of the 26 GHz – 34 GHz CO Mapping Array Pathfinder (COMAP 2.5M). The funding of COMAP was particularly important since it demonstrated in the wake of the NSF decline of the CARMA proposal (2014) that the US astronomy community and the NSF were prepared to fund large new projects at the Owens Valley Radio Observatory (OVRO), enabling the OVRO to re-establish itself as a world-class radio observatory and convincing Caltech to continue its funding of the OVRO. It is no exaggeration that the KISS coherent detector program played THE major role in saving the OVRO. The position of the CRAL and of the OVRO is now very strong and the staff, decimated by the CARMA decline, is being rebuilt and is once more at a robust strength. Two new multi-national partnerships – the Radio Astronomy Partnership (RAP) and the MMIC Partnership (MMICP) have been established at Caltech as a direct result of the KISS investment in creating the CRAL, and these are providing independent funding to OVRO and the CRAL. There are now eight agency-funded programs at the OVRO and we are optimistic about the prospects of having two more programs funded in the next year, in view of important science breakthroughs at OVRO over the last 6 months
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