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Training the Fetal Immune System Through Maternal Inflammation-A Layered Hygiene Hypothesis.
Over the last century, the alarming surge in allergy and autoimmune disease has led to the hypothesis that decreasing exposure to microbes, which has accompanied industrialization and modern life in the Western world, has fundamentally altered the immune response. In its current iteration, the "hygiene hypothesis" suggests that reduced microbial exposures during early life restricts the production and differentiation of immune cells suited for immune regulation. Although it is now well-appreciated that the increase in hypersensitivity disorders represents a "perfect storm" of many contributing factors, we argue here that two important considerations have rarely been explored. First, the window of microbial exposure that impacts immune development is not limited to early childhood, but likely extends into the womb. Second, restricted microbial interactions by an expectant mother will bias the fetal immune system toward hypersensitivity. Here, we extend this discussion to hypothesize that the cell types sensing microbial exposures include fetal hematopoietic stem cells, which drive long-lasting changes to immunity
Participatory design, beyond the local
This workshop aims at stimulating and opening a debate around the capacity of Participatory Design (PD) and other co-design approaches to deliver outcomes and methodologies that can have an impact and value for reuse well beyond the local context in which they were originally developed. This will be achieved by stimulating the submission of position papers by researchers from the PD community and beyond.These papers will be discussed during the workshop in order to identify challenges, obstacles but also potentials for scaling up PD processes and results from the local to the global.</p
Detecting Neutrino Magnetic Moments with Conducting Loops
It is well established that neutrinos have mass, yet it is very difficult to
measure those masses directly. Within the standard model of particle physics,
neutrinos will have an intrinsic magnetic moment proportional to their mass. We
examine the possibility of detecting the magnetic moment using a conducting
loop. According to Faraday's Law of Induction, a magnetic dipole passing
through a conducting loop induces an electromotive force, or EMF, in the loop.
We compute this EMF for neutrinos in several cases, based on a fully covariant
formulation of the problem. We discuss prospects for a real experiment, as well
as the possibility to test the relativistic formulation of intrinsic magnetic
moments.Comment: 6 pages, 4 b/w figures, uses RevTe
Some remarks on the visible points of a lattice
We comment on the set of visible points of a lattice and its Fourier
transform, thus continuing and generalizing previous work by Schroeder and
Mosseri. A closed formula in terms of Dirichlet series is obtained for the
Bragg part of the Fourier transform. We compare this calculation with the
outcome of an optical Fourier transform of the visible points of the 2D square
lattice.Comment: 9 pages, 3 eps-figures, 1 jpeg-figure; updated version; another
article (by M. Baake, R. V. Moody and P. A. B. Pleasants) with the complete
solution of the spectral problem will follow soon (see math.MG/9906132
Arsenic in Groundwater Sources from Selected Communities Surrounding Taal Volcano, Philippines: An Exploratory Study
Arsenic (As) is a highly toxic, carcinogenic trace metal that can potentially contaminate groundwater sources in volcanic regions. This study provides the first comparative documentation of As concentrations in groundwater in a volcano-sedimentary region in the Philippines. Matched, repeated As measurements and physico-chemical analyses were performed in 26 individual wells from 11 municipalities and city in Batangas province from July 2020 to November 2021. Using the electrothermal atomic absorption spectrometric method, analysis of the wells revealed that in 2020, 23 out of 26 (88.46%) had As levels above the WHO limit of \u3e10 ppb while 20 out of 26 wells (76.92%) had persistently high As levels a year later. Using a Wilcoxon signed-rank test, levels of As were found to be statistically elevated compared to the national safe limit of 10 pbb in the 26 matched sampling sites in both 2020 (p-value \u3c 0.001) and 2021 (p-value = 0.013). Additionally, a two-paired Wilcoxon signed-rank test revealed that As levels were statistically higher in 2020 than in 2021 (p-value = 0.003), suggesting that As levels may be higher in years when there is more volcanic activity; however, this remains to be further elucidated with suitable longitudinal data, as this study is still in its preliminary stages. The data was also analyzed using a bivariable regression, which showed no evidence of a significant relationship between As levels and distance from the danger zone (Taal volcano crater); however, results showed an inverse but statistically insignificant relationship between As levels and elevation. Due to the toxic profile and persistence of As in groundwater in Batangas Province, continuous groundwater As monitoring, timely public health risk communication, and the provision of alternative water sources to affected populations are recommended
Arsenic in Groundwater Sources from Selected Communities Surrounding Taal Volcano, Philippines: An Exploratory Study
Arsenic (As) is a highly toxic, carcinogenic trace metal that can potentially contaminate groundwater sources in volcanic regions. This study provides the first comparative documentation of As concentrations in groundwater in a volcano-sedimentary region in the Philippines. Matched, repeated As measurements and physico-chemical analyses were performed in 26 individual wells from 11 municipalities and city in Batangas province from July 2020 to November 2021. Using the electrothermal atomic absorption spectrometric method, analysis of the wells revealed that in 2020, 23 out of 26 (88.46%) had As levels above the WHO limit of \u3e10 ppb while 20 out of 26 wells (76.92%) had persistently high As levels a year later. Using a Wilcoxon signed-rank test, levels of As were found to be statistically elevated compared to the national safe limit of 10 pbb in the 26 matched sampling sites in both 2020 (p-value \u3c 0.001) and 2021 (p-value = 0.013). Additionally, a two-paired Wilcoxon signed-rank test revealed that As levels were statistically higher in 2020 than in 2021 (p-value = 0.003), suggesting that As levels may be higher in years when there is more volcanic activity; however, this remains to be further elucidated with suitable longitudinal data, as this study is still in its preliminary stages. The data was also analyzed using a bivariable regression, which showed no evidence of a significant relationship between As levels and distance from the danger zone (Taal volcano crater); however, results showed an inverse but statistically insignificant relationship between As levels and elevation. Due to the toxic profile and persistence of As in groundwater in Batangas Province, continuous groundwater As monitoring, timely public health risk communication, and the provision of alternative water sources to affected populations are recommended
Spin-dependent electron-impurity scattering in two-dimensional electron systems
We present a theoretical study of elastic spin-dependent electron scattering
caused by a charged impurity in the vicinity of a two-dimensional electron gas.
We find that the symmetry properties of the spin-dependent differential
scattering cross section are different for an impurity located in the plane of
the electron gas and for one at a finite distance from the plane. We show that
in the latter case asymmetric (`skew') scattering can arise if the polarization
of the incident electron has a finite projection on the plane spanned by the
normal vector of the two-dimensional electron gas and the initial propagation
direction. In specially preparated samples this scattering mechanism may give
rise to a Hall-like effect in the presence of an in-plane magnetic field.Comment: 4.1 pages, 2 figure
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