In neutron electric dipole moment experiments, 199Hg is used as a comagnetometer. The comagnetometer suffers from a false EDM arising in leading order from a gradient dBz/dz in the magnetic field. ...Our work concerns higher-order multipole corrections to the false EDM of 199Hg. We show that for spherical traps, all higher-order multipole are identically zero. We further show that for the usual cylindrical traps used in EDM experiments, selection of quasi-spherical dimensions for the trap can reduce the higher-order contributions. The results are another indication that trap geometry is an important consideration for experiments desiring to control this systematic effect.
We report the performance of a magnetically silent optically pumped cesium magnetometer with a statistical sensitivity of 3.9 pT and a stability of 90 fT over 150 seconds of measurement. Optical ...pumping with coherent, linearly-polarized, resonant light leads to a relatively long-lived polarized ground state of the cesium vapour contained in a measurement cell. The state precesses at its Larmor frequency in the magnetic field to be measured. Nonlinear magneto-optical rotation then leads to the rotation of the plane of polarization of a linearly polarized probe laser beam. The rotation angle is modulated at twice the Larmor frequency. A measurement of this frequency constitutes an absolute measurement of the magnetic field magnitude. Featuring purely optical operation, non-magnetic construction, low noise floor, and high stability, this sensor will be used for the upcoming TUCAN electric dipole moment experiment and other highly sensitive magnetic applications.
The TRIUMF Ultra-Cold Advanced Neutron (TUCAN) collaboration aims at a precision neutron electric dipole moment (nEDM) measurement with an uncertainty of \(10^{-27}\,e\cdot\mathrm{cm}\), which is an ...order-of-magnitude better than the current nEDM upper limit and enables us to test Supersymmetry. To achieve this precision, we are developing a new high-intensity ultracold neutron (UCN) source using super-thermal UCN production in superfluid helium (He-II) and a nEDM spectrometer. The current development status of them is reported in this article.
A passive magnetic shield was designed and constructed for magnetometer tests for the future neutron electric dipole moment experiment at TRIUMF. The axial shielding factor of the magnetic shield was ...measured using a magnetometer based on non-linear magneto-optical rotation of the plane of polarized laser light upon passage through a paraffin-coated vapour cell containing natural Rb at room temperature. The laser was tuned to the Rb D1 line, near the \(^{85}\)Rb \(F=2\rightarrow 2,3\) transition. The shielding factor was measured by applying an axial field externally and measuring the magnetic field internally using the magnetometer. The axial shielding factor was determined to be \((1.3\pm 0.1)\times 10^{7}\), from an applied axial field of 1.45~\(\mu\)T in the background of Earth's magnetic field.
Up to now, the role of particle sizes on the impact behavior of ceramic particles in aerosol deposition not yet fully understood. Hence, with the aim to supply a more general understanding, modeling ...series of low strain rate compression and high-speed impact were performed by molecular dynamics on single-crystalline particles in sizes of 10-300 nm that are tuned to match mechanical properties of TiO
2
-anatase. The modeling results reveal that particles with original diameter of 25-75 nm exhibit three different impact behaviors that could be distinguished as (i) rebounding, (ii) bonding and (iii) fragmentation, depending on their initial impact velocity. In contrast, particles larger than 75 nm do not exhibit the bonding behavior. Detailed stress and strain field distributions reveal that combination of “localized inelastic deformation” along the slip systems and “shear localization” cause bonding of the small and large particles to the substrate. The analyses of associated temperature rise by the inelastic deformation revealed that heat diffusion at these small scales depend on size. Whereas small particles could reach a rather homogeneous temperature distribution, the evolved heat in the larger ones keeps rather localized to areas of highest deformation and may support deformation and the formation of dense layers in aerosol deposition.
Scale formation, the deposition of certain minerals such as CaCO3, MgCO3, and CaSO4·2H2O in industrial facilities and household devices, leads to reduced efficiency or severe damage. Therefore, ...incrustation is a major problem in everyday life. In recent years, double hydrophilic block copolymers (DHBCs) have been the focus of interest in academia with regard to their antiscaling potential. In this work, we synthesized well-defined blocklike PAA-PAMPS copolymers consisting of acrylic acid (AA) and 2-acrylamido-2-methyl-propane sulfonate (AMPS) units in a one-step reaction by RAFT polymerization. The derived copolymers had dispersities of 1.3 and below. The copolymers have then been investigated in detail regarding their impact on the different stages of the crystallization process of CaCO3. Ca2+ complexation, the first step of a precipitation process, and polyelectrolyte stability in aqueous solution have been investigated by potentiometric measurements, isothermal titration calorimetry (ITC), and dynamic light scattering (DLS). A weak Ca2+ induced copolymer aggregation without concomitant precipitation was observed. Nucleation, early particle growth, and colloidal stability have been monitored in situ with DLS. The copolymers retard or even completely suppress nucleation, most probably by complexation of solution aggregates. In addition, they stabilize existing CaCO3 particles in the nanometer regime. In situ AFM was used as a tool to verify the coordination of the copolymer to the calcite (104) crystal surface and to estimate its potential as a growth inhibitor in a supersaturated CaCO3 environment. All investigated copolymers instantly stopped further crystal growth. The carboxylate richest copolymer as the most promising antiscaling candidate proved its enormous potential in scale inhibition as well in an industrial-filming test (Fresenius standard method).
BACKGROUNDProstaglandin E2 (PGE2) increases pulmonary vascular permeability by activation of the PGE2 receptor 3 (EP3), which may explain adverse pulmonary effects of the EP1/EP3 receptor agonist ...sulprostone in patients. In addition, PGE2 contributes to pulmonary oedema in response to platelet-activating factor (PAF). PAF increases endothelial permeability by recruiting the cation channel transient receptor potential canonical 6 (TRPC6) to endothelial caveolae via acid sphingomyelinase (ASMase). Yet, the roles of PGE2 and EP3 in this pathway are unknown. We hypothesised that EP3 receptor activation may increase pulmonary vascular permeability by activation of TRPC6, and thus, synergise with ASMase-mediated TRPC6 recruitment in PAF-induced lung oedema. METHODSIn isolated lungs, we measured increases in endothelial calcium (ΔCa2+) or lung weight (Δweight), and endothelial caveolar TRPC6 abundance as well as phosphorylation. RESULTSPAF-induced ΔCa2+ and Δweight were attenuated in EP3-deficient mice. Sulprostone replicated PAF-induced ΔCa2+ and Δweight which were blocked by pharmacological/genetic inhibition of TRPC6, ASMase or Src-family kinases (SrcFK). PAF, but not sulprostone, increased TRPC6 abundance in endothelial caveolae. Immunoprecipitation revealed PAF- and sulprostone-induced tyrosine-phosphorylation of TRPC6 that was prevented by inhibition of phospholipase C (PLC) or SrcFK. PLC inhibition also blocked sulprostone-induced ΔCa2+ and Δweight, as did inhibition of SrcFK or inhibitory G-protein (Gi) signalling. CONCLUSIONSEP3 activation triggers pulmonary oedema via Gi-dependent activation of PLC and subsequent SrcFK-dependent tyrosine phosphorylation of TRPC6. In PAF-induced lung oedema, this TRPC6 activation coincides with ASMase-dependent caveolar recruitment of TRPC6, resulting in rapid endothelial Ca2+ influx and barrier failure.
Background
Prostaglandin E
2
(PGE
2
) increases pulmonary vascular permeability by activation of the PGE
2
receptor 3 (EP
3
), which may explain adverse pulmonary effects of the EP
1
/EP
3
receptor ...agonist sulprostone in patients. In addition, PGE
2
contributes to pulmonary oedema in response to platelet-activating factor (PAF). PAF increases endothelial permeability by recruiting the cation channel transient receptor potential canonical 6 (TRPC6) to endothelial caveolae
via
acid sphingomyelinase (ASMase). Yet, the roles of PGE
2
and EP
3
in this pathway are unknown. We hypothesised that EP
3
receptor activation may increase pulmonary vascular permeability by activation of TRPC6, and thus, synergise with ASMase-mediated TRPC6 recruitment in PAF-induced lung oedema.
Methods
In isolated lungs, we measured increases in endothelial calcium (ΔCa
2+
) or lung weight (Δweight), and endothelial caveolar TRPC6 abundance as well as phosphorylation.
Results
PAF-induced ΔCa
2+
and Δweight were attenuated in EP
3
-deficient mice. Sulprostone replicated PAF-induced ΔCa
2+
and Δweight which were blocked by pharmacological/genetic inhibition of TRPC6, ASMase or Src-family kinases (SrcFK). PAF, but not sulprostone, increased TRPC6 abundance in endothelial caveolae. Immunoprecipitation revealed PAF- and sulprostone-induced tyrosine-phosphorylation of TRPC6 that was prevented by inhibition of phospholipase C (PLC) or SrcFK. PLC inhibition also blocked sulprostone-induced ΔCa
2+
and Δweight, as did inhibition of SrcFK or inhibitory G-protein (G
i
) signalling.
Conclusions
EP
3
activation triggers pulmonary oedema
via
G
i
-dependent activation of PLC and subsequent SrcFK-dependent tyrosine phosphorylation of TRPC6. In PAF-induced lung oedema, this TRPC6 activation coincides with ASMase-dependent caveolar recruitment of TRPC6, resulting in rapid endothelial Ca
2+
influx and barrier failure.
Aerosol deposition (AD) enables the formation of dense ceramic coatings by high velocity impact of submicron‐sized particles. However, up to now, it is still not clear how the material properties of ...the ceramic powder particles influence their impact behavior and possible success in layer build‐up in AD. Therefore, in order to provide a broader understanding, this study utilizes molecular dynamic (MD) simulations to investigate the impacts of single‐crystalline particles while manipulating binding energies, particle sizes, and impact velocities, addressing a rather wide range of different materials and process conditions. The findings reveal that increasing binding energies from 0.22 to 0.96 eV necessitates up to three times higher velocities to reach thresholds for bonding and fragmentation, which are linked to potential layer formation. For conditions above the velocity thresholds given by individual binding energies, similarities in the deformation and fragmentation patterns are derived. Consequently, rough estimations regarding the required particle impact velocities for AD of different materials can be inferred.
The course of patients with multiple system atrophy (MSA) who undergo deep brain stimulation (DBS) is unclear. In a retrospective review of 1,496 patients with MSA evaluated at our institutions from ...1998-2021, 12 patients underwent DBS; 9 had a diagnosis of Parkinson's disease at the time of surgery. Nine patients reported initial improvement in at least one symptom and 7 experienced overall worsening following DBS. All patients had at least one red flag sign or symptom suggesting atypical parkinsonism prior to surgery. Considering overall poor outcomes of DBS in MSA, we recommend careful consideration of red flags in patient selection.
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