Method for determination of in-vitro fiber dissolution rate by direct optical measurement of diameter decrease

Α new method for measuring in vitro fiber dissolution rate in physiological saline solutions is based on direct optical measurement of fiber diameter decrease. Dissolution times measured by this new method for a variety of vitreous silicate fibers with a wide range of dissolution rates are in good agreement with results from SEM and from traditional mass loss and solution analysis techniques. The new method is conceptually and experimentally simple, and it can be applied directly to fibers pulled from the original fiber sample with no pretreatment

The effect of a new formaldehyde-free binder on the dissolution rate of glass wool fibre in physiological saline solution

The in-vitro dissolution rate of fibres is a good predictor of the in-vivo behavior and potential health effects of inhaled fibres. This study examines the effect of a new formaldehyde-free carbohydrate-polycarboxylic acid binder on the in-vitro dissolution rate of biosoluble glass fibres. Dissolution rate measurements in pH 7.4 physiological saline solution show that the presence of the binder on wool insulation glass fibres has no effect on their dissolution. There is no measurable difference between the dissolution rates of continuous draw fibres before and after binder was applied by dipping. Nor is there a measurable difference between the dissolution rates of a production glass wool sample with binder and that same sample after removal of the binder by low-temperature ashing. Morphological examination shows that swelling of the binder in the solution is at least partially responsible for the development of open channels around the glass-binder interface early in the dissolution. These channels allow fluid to reach the entire glass surface under the binder coating. There is no evidence of any delay in the dissolution rate as a result of the binder coating

The Tetravalent Manganese Oxides : Clarification of their Structural Variations and Relationships and Characterization of their Occurrence in the Terrestrial Weathering Environment as Desert Varnish and other Manganese Oxide Concentrations

A number of structural problems in the mineralogy of the tetravalent manganese oxides have been addressed by infrared spectroscopy in conjunction with X-ray diffraction and chemical analysis. The first pyrolusite with proven orthorhombic symmetry is reported. Examination of pyrolusites with different degrees of orthorhombic distortion supports the view that this distortion is the result of micro-pores within the crystal. Pyrolusite infrared spectra exhibit variations which cannot be correlated to orthorhombic distortion, ramsdellite intergrowths, or other mineral impurity. The continuous structural variation of the nsutites from a rarnsdellite end-member to a pyrolusite end-member has been confirmed although much of the variation in synthetic nsutites appears to be related to crystalline order. Ramsdellite has a single, crystallographically-ordered type of water, which appears to be an integral part of the structure. The only hydrous component of romanechite is water, which is located in the channels in a specific crystallographic site. The only hydrous component of lithiophorite is hydroxide ion, which is oriented perpendicular to the cleavage planes. Birnessite appears to have a layer structure on the basis of its infrared spectrum. Its identity with proposed synthetic analogs is confirmed. Todorokite is a valid mineral species which is not analogous to any synthetic phases or to any alteration products of them. It appears to have a layered structure. Rancieite probably has a layer structure related to birnessite. It is possible to distinguish manganese oxides of different structural groups from one another by their spectra in the mid-infrared region, which is sensitive to the hydrous components and the manganese octahedral framework. Because of its sensitivity to short range order, infrared spectroscopy is often superior to X-ray diffraction for the determinative mineralogy of the manganese oxides, which often occur in a finely-particulate, poorly-crystalline state. Spectra in the region 4000 cm⁻¹ to 200 cm⁻¹ are presented for well-characterized manganese oxide samples in order to form a basis for identification of manganese oxide mineralogy. The following oxides are included: aurorite, birnessite, braunite, buserite, chalcophanite, coronadite, cryptomelane, groutite, hausmannite, hollandite, lithiophorite, manganite, manganosite, manjiroite, marokite, nsutite, partridgeite, pyrolusite, quenselite, ramsdellite, rancieite, romanechite (psilomelane), todorokite, and woodruffite. This data base has been applied to the study of the mineralogy of manganese oxide concentrations of the terrestrial weathering environment. Through the integrated application of a variety of infrared spectroscopic, X-ray diffraction, electron optic, and chemical techniques, the characteristic mineralogy of desert varnish has been identified as bimessite, hematite, and mixed-layer illite-montmorillonite clay minerals. Clay minerals comprise greater than 70 percent of the varnish, the oxides constitute t he bulk of the remainder and are in intimate physical association with the clays. An abrupt change in chemistry, mineralogy, and morphology exists at the varnish-rock interface. The origin of the material is external to the rock which it coats. The clays are most likely transported by wind or water. The oxides appear to be transported by water. Clay minerals are necessary for varnish formation, probably through their influence on oxide concentration or deposition. Morphological distinctions among desert varnish, manganese dendrites, river deposits and other manganese oxide concentrations of the terrestrial weathering environment have a sound basis in differences in their mineralogy. The manganese oxide in manganese dendrites is either romanechite or a hollandite group mineral. These are mixed with varying amounts of silicate minerals, which are a passive substrate for the oxide deposition. Manganese stream deposits are generally birnessite with minor amounts of silicate minerals; one nsutite stream deposit has been identified. Crack deposit mineralogy resembles that of manganese dendrites. Cave and subglacial deposit mineralogy resembles that of manganese stream deposits. No dendrite has been found to consist of pyrolusite. Hydropsilomelane concretions, which carry chemical remanent magnetization in sediments in Baja California, Mexico, consist of siltstone matrix minerals cemented by a manganese oxide having the chalcophanite structure. The high concentration of magnesium presumed to occur in the interlayer position of this mineral extends the known range of substitution in chalcophanite-structure minerals.</p

Polymorphism in TGFB1 is associated with worse non-relapse mortality and overall survival after stem cell transplantation with unrelated donors.

Transforming growth factor beta-1, encoded by the TGFB1 gene, is a cytokine that plays a central role in many physiological and pathogenic processes. We have sequenced TGFB1 regulatory region and assigned allelic genotypes in a large cohort of hematopoietic stem cell transplantation patients and donors. In this study, we analyzed 522 unrelated donor-patient pairs and examined the combined effect of all the common polymorphisms in this genomic region. In univariate analysis, we found that patients carrying a specific allele, 'p001', showed significantly reduced overall survival (5-year overall survival 30.7% for p001/ p001 patients vs. 41.6% others; P=0.032) and increased non-relapse mortality (1-year nonrelapse mortality: 39.0% vs. 25.4%; P=0.039) after transplantation. In multivariate analysis, the presence of a p001/ p001 genotype in patients was confirmed as an independent factor for reduced overall survival [hazard ratio=1.53 (1.04-2.24); P=0.031], and increased non-relapse mortality [hazard ratio=1.73 (1.06-2.83); P=0.030]. In functional experiments we found a trend towards a higher percentage of surface transforming growth factor beta-1-positive regulatory T cells after activation when the cells had a p001 allele (P=0.07). Higher or lower production of transforming growth factor beta-1 in the inflammatory context of hematopoietic stem cell transplantation may influence the development of complications in these patients. Findings indicate that TGFB1 genotype could potentially be of use as a prognostic factor in hematopoietic stem cell transplantation risk assessment algorithms

Single cell analysis identifies <em>CRLF2</em> rearrangements as both early and late events in Down syndrome and non-Down syndrome acute lymphoblastic leukaemia

Deregulated expression of the type I cytokine receptor, CRLF2, is observed in 5-15% of precursor B-cell acute lymphoblastic leukaemia (B-ALL). We have previously reported the genomic landscape of patients with CRLF2 rearrangements (CRLF2-r) using both whole genome and exome sequencing, which identified a number of potential clonal and sub-clonal genomic alterations. In this study, we aimed to assess when the CRLF2-r; IGH-CRLF2 or P2RY8-CRLF2, arose during the evolution of both Down syndrome-ALL (DS-ALL) and non-DS-ALL. Using fluorescence in situ hybridisation, we were able to track up to four structural variants in single cells from 47 CRLF2-r B-ALL patients, which in association with our multiplex single cell analysis of a further four patients, permitted simultaneous tracking of copy number alterations, structural and single nucleotide variants within individual cells. We observed CRLF2-r arising as both early and late events in DS and non-DS-ALL patients. Parallel evolution of discrete clones was observed in the development of CRLF2-r B-ALL, either involving the CRLF2-r or one of the other tracked abnormalities. In depth single cell analysis identified both linear and branching evolution with early clones harbouring a multitude of abnormalities, including the CRLF2-r in DS-ALL patients

'Diverse mobilities': second-generation Greek-Germans engage with the homeland as children and as adults

This paper is about the children of Greek labour migrants in Germany. We focus on two life-stages of ‘return’ for this second generation: as young children brought to Greece on holidays or sent back for longer periods, and as young adults exercising an independent ‘return’ migration. We draw both on literature and on our own field interviews with 50 first- and second-generation Greek-Germans. We find the practise of sending young children back to Greece to have been surprisingly widespread yet little documented. Adult relocation to the parental homeland takes place for five reasons: (i) a ‘search for self’; (ii) attraction of the Greek way of life; (iii) the actualisation of the ‘family narrative of return’ by the second, rather than the first, generation; (iv) life-stage events such as going to university or marrying a Greek; (v) escape from a traumatic event or oppressive family situation. Yet the return often brings difficulties, disillusionment, identity reappraisal, and a re-evaluation of the German context

Distribution and Compositional Variations of Plasma Ions in Mercury's Space Environment: The First Three Mercury Years of MESSENGER Variations

We have analyzed measurements of planetary ions near Mercury made by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) Fast Imaging Plasma Spectrometer (FIPS) over the first three Mercury years of orbital observations (25 March 2011 through 31 December 2011). We determined the composition and spatial distributions of the most abundant species in the regions sampled by the MESSENGER spacecraft during that period. In particular, we here focus on altitude dependence and relative abundances of species in a variety of spatial domains. We used observed density as a proxy for ambient plasma density, because of limitations to the FIPS field of view. We find that the average observed density is 3.9 × 10-2 cm-3 for He2+, 3.4 × 10-4 cm-3 for He+, 8.0 × 10-4 cm-3 for O+-group ions, and 5.1 × 10-3 cm-3 for Na+-group ions. Na+-group ions are particularly enhanced over other planetary ions (He+ and O+ group) in the northern magnetospheric cusp (by a factor of ~2.0) and in the premidnight sector on the nightside (by a factor of ~1.6). Within 30 degrees of the equator, the average densities of all planetary ions are depressed at the subsolar point relative to the dawn and dusk terminators. The effect is largest for Na+-group ions, which are 49% lower in density at the subsolar point than at the terminators. This depression could be an effect of the FIPS energy threshold. The three planetary ion species considered show distinct dependences on altitude and local time. The Na+ group has the smallest e-folding height at all dayside local times, whereas He+ has the largest. At the subsolar point, the e-folding height for Na+-group ions is 590 km, and that for the O+ group and He+ is 1100 km. On the nightside and within 750 km of the geographic equator, Na+-group ions are enhanced in the premidnight sector. This enhancement is consistent with nonadiabatic motion and may be observational evidence that nonadiabatic effects are important in Mercury's magnetosphere

JME 4110 Mechanical Engineering Design Project - Combination Machining Tool

Design and build a portable sized tool for machining relatively small parts out of metal. Ideally, a student could keep it in their dorm and bring it to an appropriate work space when he/she is ready to use it

In-vitro dissolution of vitreous silicate fibres according to EURIMA test guideline - Results of two Round Robins

The EURIMA (The European Insulation Manufacturers Association) test guideline "In-vitro acellular dissolution of man-made vitreous silicate fibres" provides a state-of-the-art method for measuring in-vitro dissolution rates relevant for evaluating the biopersistence of insulation wool fibres and other vitreous silicate fibres. Based on this guideline two Round Robins were conducted as well as specific investigations on the influence of selected test parameters. Nine and six laboratories, respectively, participated in the two Round Robins. The standard deviation between Kdis results obtained by different laboratories was slightly lower in the second Round Robin ranging from 24 to 61 % (highest for the low-soluble fibres). The relatively high inter-laboratory variation suggests that the equipment, setup and procedures should be specified in much more detail in a future test method. Key parameters to be kept constant are flow rate/surface area and liquid composition, and care should be taken to maintain constant conditions and eliminate outlier measurements. Α laboratory may use the method described in the guideline for quality assurance of maintained biosolubility and for development of alternative fibre modifications as the method is well suited for ranking different fibres with respect to dissolution coefficients within one laboratory. However, caution should be exercised when comparing values obtained by one laboratory to values obtained by another