764 research outputs found
Clinical and laboratory features of mesenchymal stromal cells in pediatric stem cell transplantation
This thesis describes the clinical use and laboratory findings of bone marrow (BM) derived, ex-vivo expanded human Mesenchymal Stromal Cells (MSCs) in pediatric stem cell transplantation. Advances in transplant technologies have permitted the use of __alternative donors__, i.e. haploidentical peripheral blood stem cells and umbilical cord blood, as a source of donor hematopoietic stem cells. MSCs located in the bone marrow form the stromal network, essential for the support of normal hematopoietic stem cell growth and development. Methods to expand MSCs sufficient for clinical uses have recently become available. In vitro experiments show MSCs interact with various cells of both the innate and adaptive immune system, which overall results in the induction of an anti-inflammatory state. The ability of MSCs to support hematopoietic stem cell growth coupled with their potent immune suppressive effects mean that they are ideal candidate cells to explore in the context of overcoming some of the problems specifically associated with the use of alternative donors. In this thesis, we therefore attempted to address the most relevant of these issues that, given the known properties of MSCs, would allow us to assess the possible usefulness of MSCs as an innovative strategy to resolve them.Willem Alexander Kinder en Jeugd Centrum, Pfizer BV, Genzyme Nederland, Amgen BV, Gilead Sciences BVUBL - phd migration 201
On selection criteria for problems with moving inhomogeneities
We study mechanical problems with multiple solutions and introduce a
thermodynamic framework to formulate two different selection criteria in terms
of macroscopic energy productions and fluxes. Studying simple examples for
lattice motion we then compare the implications for both resting and moving
inhomogeneities.Comment: revised version contains new introduction, numerical simulations of
Riemann problems, and a more detailed discussion of the causality principle;
18 pages, several figure
Toward Elucidating the Human Gut Microbiota-Brain Axis: Molecules, Biochemistry, and Implications for Health and Diseases
In recent years, a substantial amount of data have supported an active role of gut microbiota in mediating mammalian brain function and health. Mining gut microbiota and their metabolites for neuroprotection is enticing but requires that the fundamental biochemical details underlying such microbiota-brain crosstalk be deciphered. While a neuronal gut-brain axis (through the vagus nerve) is not disputable, accumulating studies also point to a humoral route (via blood/lymphatic circulation) by which innumerable microbial molecular cues translocate from local gut epithelia to circulation with potentials to further cross the blood-brain barrier and reach the brain. In this Perspective, we review a realm of gut microbial molecules to evaluate their fate, function, and neuroactivities in vivo as mediated by microbiota. We turn to seminal studies of neurophysiology and neurologic disease models for the elucidation of biochemical pathways that link microbiota to gut-brain signaling. In addition, we discuss opportunities and challenges for advancing the microbiota-brain axis field while calling for high-throughput discovery of microbial molecules and studies for resolving the interspecies, interorgan, and interclass interaction among these neuroactive microbial molecules
The Quark-Photon Vertex and the Pion Charge Radius
The rainbow truncation of the quark Dyson-Schwinger equation is combined with
the ladder Bethe-Salpeter equation for the dressed quark-photon vertex to study
the low-momentum behavior of the pion electromagnetic form factor. With model
gluon parameters previously fixed by the pion mass and decay constant, the pion
charge radius is found to be in excellent agreement with the data. When
the often-used Ball-Chiu Ansatz is used to construct the quark-photon vertex
directly from the quark propagator, less than half of is generated.
The remainder of is seen to be attributable to the presence of the
-pole in the solution of the ladder Bethe-Salpeter equation.Comment: 21 pages, 9 figure
Study of the radiative decay with CMD-2 detector
Using the of data collected with the CMD-2 detector at VEPP-2M
the decay mode , has been
studied. The obtained branching ratio is B(.Comment: 13 pages, 5 figures, LaTex2e, to be published in Phys. Lett.
Balanced realizations of discrete-time stable all-pass systems and the tangential Schur algorithm
In this paper, the connections are investigated between two different
approaches towards the parametrization of multivariable stable all-pass systems
in discrete-time. The first approach involves the tangential Schur algorithm,
which employs linear fractional transformations. It stems from the theory of
reproducing kernel Hilbert spaces and enables the direct construction of
overlapping local parametrizations using Schur parameters and interpolation
points. The second approach proceeds in terms of state-space realizations. In
the scalar case, a balanced canonical form exists that can also be parametrized
by Schur parameters. This canonical form can be constructed recursively, using
unitary matrix operations. Here, this procedure is generalized to the
multivariable case by establishing the connections with the first approach. It
gives rise to balanced realizations and overlapping canonical forms directly in
terms of the parameters used in the tangential Schur algorithm
Granulocyte concentrates: Prolonged functional capacity during storage in the presence of phenotypic changes
Background Granulocyte transfusion has been proposed as a bridging therapy for patients with prolonged p
Relationship between ecosystem productivity and photosynthetically active radiation for northern peatlands
We analyzed the relationship between new ecosystem exchange of carbon dioxide (NEE) and irradiance (as photosynthetic photon flux density of PPFD), using published and unpublished data that have been collected during midgrowing season for carbon balance studies at seven peatlands in North America and Europe. NEE measurements included both eddy-correlation tower and clear, static chamber methods, which gave very similar results. Data were analyzed by site, as aggregated data set for all peatland type (bog, poor fen, rich fen, and all fens) and as a single aggregated data set for all peatlands. In all cases, a fit with a rectangular hyperbola (NEE = PPFD P max (PPFD + PMAX) + R) better described the NEE-PPFD relationships ,while bogs had lower respiration rates (R = -2.0 umol m-2 s-1 for bogs and -2.7 umol m-2 s-1 for fens) and lower NEE at moderate and high light levels (Pmax = 5.2 umol m-2 s-1) than the upland exosystems (closed canopy forest, grassland, and cropland) summarized by Ruimy et al. [1995]. Despite this low productivity, northern peatland soil carbon pools are generally 5-50 times larger than upland ecosystems because of slow rates of decomposition caused by litter quality and anaerobic, cold soils
Conformal mapping methods for interfacial dynamics
The article provides a pedagogical review aimed at graduate students in
materials science, physics, and applied mathematics, focusing on recent
developments in the subject. Following a brief summary of concepts from complex
analysis, the article begins with an overview of continuous conformal-map
dynamics. This includes problems of interfacial motion driven by harmonic
fields (such as viscous fingering and void electromigration), bi-harmonic
fields (such as viscous sintering and elastic pore evolution), and
non-harmonic, conformally invariant fields (such as growth by
advection-diffusion and electro-deposition). The second part of the article is
devoted to iterated conformal maps for analogous problems in stochastic
interfacial dynamics (such as diffusion-limited aggregation, dielectric
breakdown, brittle fracture, and advection-diffusion-limited aggregation). The
third part notes that all of these models can be extended to curved surfaces by
an auxilliary conformal mapping from the complex plane, such as stereographic
projection to a sphere. The article concludes with an outlook for further
research.Comment: 37 pages, 12 (mostly color) figure
Thermally stable perovskite solar cells by all-vacuum deposition
Vacuum deposition is a solvent-free method suitable for growing thin films of metal halide perovskite (MHP) semiconductors. However, most reports of high-efficiency solar cells based on such vacuum-deposited MHP films incorporate solution-processed hole transport layers (HTLs), thereby complicating prospects of industrial upscaling and potentially affecting the overall device stability. In this work, we investigate organometallic copper phthalocyanine (CuPc) and zinc phthalocyanine (ZnPc) as alternative, low-cost, and durable HTLs in all-vacuum-deposited solvent-free formamidinium-cesium lead triodide [CH(NH2)2]0.83Cs0.17PbI3 (FACsPbI3) perovskite solar cells. We elucidate that the CuPc HTL, when employed in an "inverted"p-i-n solar cell configuration, attains a solar-to-electrical power conversion efficiency of up to 13.9%. Importantly, unencapsulated devices as large as 1 cm2 exhibited excellent long-term stability, demonstrating no observable degradation in efficiency after more than 5000 h in storage and 3700 h under 85 °C thermal stressing in N2 atmosphere
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