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Tumor necrosis factor-alpha regulates the expression of inducible costimulator receptor ligand on CD34+ progenitor cells during differentiation into antigen presenting cells
The inducible costimulator receptor (ICOS) is a third member of the CD28 receptor family that regulates T cell activation and function. ICOS binds to a newly identified ligand on antigen presenting cells different from the CD152 ligands CD80 and CD86. We used soluble ICOSIg and a newly developed murine anti-human ICOS ligand (ICOSL) monoclonal antibody to further characterize the ICOSL during ontogeny of antigen presenting cells. In a previous study, we found that ICOSL is expressed on monocytes, dendritic cells, and B cells. To define when ICOSL is first expressed on myeloid antigen presenting cells, we examined ICOSL expression on CD34 cells in bone marrow. We found that CD34bright cells regardless of their myeloid commitment were ICOSL , whereas ICOSL was first expressed when CD34 expression diminished and the myeloid marker CD33 appeared
Gyroscopes based on nitrogen-vacancy centers in diamond
We propose solid-state gyroscopes based on ensembles of negatively charged
nitrogen-vacancy () centers in diamond. In one scheme, rotation of
the nitrogen-vacancy symmetry axis will induce Berry phase shifts in the electronic ground-state coherences proportional to the solid angle
subtended by the symmetry axis. We estimate sensitivity in the range of
in a 1 sensor volume using
a simple Ramsey sequence. Incorporating dynamical decoupling to suppress
dipolar relaxation may yield sensitivity at the level of . With a modified Ramsey scheme, Berry phase shifts in the
hyperfine sublevels would be employed. The projected sensitivity
is in the range of , however the smaller
gyromagnetic ratio reduces sensitivity to magnetic-field noise by several
orders of magnitude. Reaching would represent
an order of magnitude improvement over other compact, solid-state gyroscope
technologies.Comment: 3 figures, 5 page
Temperature dependence of the nitrogen-vacancy magnetic resonance in diamond
The temperature dependence of the magnetic resonance spectra of
nitrogen-vacancy (NV-) ensembles in the range of 280-330 K was studied. Four
samples prepared under different conditions were studied with NV-
concentrations ranging from 10 ppb to 15 ppm. For all of these samples, the
axial zero-field splitting (ZFS) parameter, D, was found to vary significantly
with temperature, T, as dD/dT = -74.2(7) kHz/K. The transverse ZFS parameter,
E, was non-zero (between 4 and 11 MHz) in all samples, and exhibited a
temperature dependence of dE/(EdT) = -1.4(3) x 10^(-4) K^(-1). The results
might be accounted for by considering local thermal expansion. The observation
of the temperature dependence of the ZFS parameters presents a significant
challenge for room-temperature diamond magnetometers and may ultimately limit
their bandwidth and sensitivity.Comment: 5 pages, 2 figures, 1 tabl
Antibody to the Ligand of CD40, Gp39, Blocks the Occurrence of the Acute and Chronic Forms of Graft-Vs-Host Disease
Physical properties of thermoelectric zinc antimonide using first-principles calculations
We report first principles calculations of the structural, electronic,
elastic and vibrational properties of the semiconducting orthorhombic ZnSb
compound. We study also the intrinsic point defects in order to eventually
improve the thermoelectric properties of this already very promising
thermoelectric material. Concerning the electronic properties, in addition to
the band structure, we show that the Zn (Sb) crystallographically equivalent
atoms are not exactly equivalent from the electronic point of view. Lattice
dynamics, elastic and thermodynamic properties are found to be in good
agreement with experiments and they confirm the non equivalency of the zinc and
antimony atoms from the vibrational point of view. The calculated elastic
properties show a relatively weak anisotropy and the hardest direction is the y
direction. We observe the presence of low energy modes involving both Zn and Sb
atoms at about 5-6 meV, similarly to what has been found in Zn4Sb3 and we
suggest that the interactions of these modes with acoustic phonons could
explain the relatively low thermal conductivity of ZnSb. Zinc vacancies are the
most stable defects and this explains the intrinsic p-type conductivity of
ZnSb.Comment: 33 pages, 8 figure
Engaging stakeholders in research to address water-energy-food (WEF) nexus challenges
The water–energy–food (WEF) nexus has become a popular, and potentially powerful, frame through which to analyse interactions and interdependencies between these three systems. Though the case for transdisciplinary research in this space has been made, the extent of stakeholder engagement in research remains limited with stakeholders most commonly incorporated in research as end-users. Yet, stakeholders interact with nexus issues in a variety of ways, consequently there is much that collaboration might offer to develop nexus research and enhance its application. This paper outlines four aspects of nexus research and considers the value and potential challenges for transdisciplinary research in each. We focus on assessing and visualising nexus systems; understanding governance and capacity building; the importance of scale; and the implications of future change. The paper then proceeds to describe a novel mixed-method study that deeply integrates stakeholder knowledge with insights from multiple disciplines. We argue that mixed-method research designs—in this case orientated around a number of cases studies—are best suited to understanding and addressing real-world nexus challenges, with their inevitable complex, non-linear system characteristics. Moreover, integrating multiple forms of knowledge in the manner described in this paper enables research to assess the potential for, and processes of, scaling-up innovations in the nexus space, to contribute insights to policy and decision making
A strategy for the characterization of minute chromosome rearrangements using multiple color fluorescence in situ hybridization with chromosome-specific DNA libraries and YAC clones
The identification of marker chromosomes in clinical and tumor cytogenetics by chromosome banding analysis can create problems. In this study, we present a strategy to define minute chromosomal rearrangements by multicolor fluorescence in situ hybridization (FISH) with whole chromosome painting probes derived from chromosome-specific DNA libraries and Alu-polymerase chain reaction (PCR) products of various region-specific yeast artificial chromosome (YAC) clones. To demonstrate the usefulness of this strategy for the characterization of chromosome rearrangements unidentifiable by banding techniques, an 8p+ marker chromosome with two extra bands present in the karyotype of a child with multiple anomalies, malformations, and severe mental retardation was investigated. A series of seven-color FISH experiments with sets of fluorochrome-labeled DNA library probes from flow-sorted chromosomes demonstrated that the additional segment on 8p+ was derived from chromosome 6. For a more detailed characterization of the marker chromosome, three-color FISH experiments with library probes specific to chromosomes 6 and 8 were performed in combination with newly established telomeric and subtelomeric YAC clones from 6q25, 6p23, and 8p23. These experiments demonstrated a trisomy 6pter6p22 and a monosomy 8pter8p23 in the patient. The present limitations for a broad application of this strategy and its possible improvements are discusse
Optimising mopane worm (<i>Gonimbrasia belina</i>) processing for improved nutritional and microbial quality
Mopane worms (Gonimbrasia belina) is an important source of food and contribute to the nutrition of people who consume them. However, the traditional processing methods may have detrimental effects on the nutritional value and should also guarantee microbial quality. In this study, the nutritional composition and microbial quality of mopane worms processed under different boiling time (0-20 min) and drying temperature (40-60 °C) conditions were investigated and optimised using response surface methodology. An increase in the boiling time at the lowest drying temperature resulted in an increase in protein content and reduction in coliform counts. The optimum conditions of boiling for 20 min and drying at 40 °C resulted in mopane worms with a protein content of 49.4% DW and coliform counts <1.5 log cfu/g. In addition, high concentrations of crude fibre (13.6% DW) and fat (20.2% DW), as well as Fe (19.0 mg/100 g) and Zn (17.9 mg/100 g) were also recorded. A decrease in the total bacterial count, Escherichia coli and yeasts and moulds at the boiling time ≥20 min irrespective of the drying temperature suggested that exposure to heat reduced the microbial growth and contamination. Reduction of the mopane worms’ moisture content (<7%) due to drying further slowed down the rate of microbial growth. The optimal processing conditions (boiling for 20 min and drying at 40 °C) are recommended for pretreatment of mopane worms prior to further processing into various products
Temperature dependence of the EPR linewidth of Yb3+ - ions in Y0.99Yb0.01Ba2Cu3OX compounds: Evidence for an anomaly near TC
Electron paramagnetic resonance experiments on doped Yb3+ ions in YBaCuO
compounds with different oxygen contents have been made. We have observed the
strong temperature dependence of the EPR linewidth in the all investigated
samples caused by the Raman processes of spin-lattice relaxation. The
spin-lattice relaxation rate anomaly revealed near TC in the superconducting
species can be assigned to the phonon density spectrum changesComment: 10 pages, 4 figures Renewed versio
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