We investigated the acquisition of thermochemical remanent magnetization (TCRM) on basaltic rocks from the volcanic island of São Tomé (Gulf of Guinea) and from the southern part of the Red Sea Rift, ...both containing homogeneous titanomagnetite grains with Curie temperatures of 100–200 °C. The TCRM was created in a rotating thermomagnetometer by cooling the samples from 570 to 200 °C at a rate of 1 °C/hr in the presence of a laboratory magnetic field of 50 μT. The TCRM acquisition occurred at high temperature T > 520 °C through the nucleation of ilmenite lamellae dividing the titanium‐magnetite cells. Mutual Fe‐Ti diffusion moved the composition of the cells closer to that of magnetite, leading to an increase in the Curie temperature Tс. The TCRM was formed at practically fixed volume of the titanomagnetite cells when Tс exceeded T. Theory indicates that the TCRM should be very close to the value of a pure thermoremanent magnetization acquired in the same field. The Thellier‐style experiments conducted on the samples bearing a laboratory induced TCRM confirmed these predictions, with palaeointensity estimates in agreement to within 5% with expected value. This conclusion radically differs from previous results obtained in the case of a pure chemical remanent magnetization and gives hope that a TCRM could be a robust source of palaeomagnetic information, yielding unbiased palaeointensity determinations.
Key Points
Thermochemical remanences in titanomagnetites are reproduced in laboratory experiments
Thermochemical remanent magnetizations yield similar intensities and close blocking temperatures spectra
Thermochemical remanent magnetization created in titanomagnetites can provide reliable absolute palaeointensity estimates
Few layers graphene has been grown on 4H-SiC. Since this material has outstanding electronic properties, we aimed fabricating graphene field-effect transistors on silicon carbide wafer. Growth of the ...graphene layers was made by e-beam sublimation of silicium under ultra high vacuum (UHV). These layers were patterned and used as channels of transistors with source and drain made of P+ SiC. The different technological steps were checked through Raman spectroscopy, Scanning Electron Microscopy (SEM), and electrical characterizations.
Homeostatic turnover of the extracellular matrix conditions the structure and function of the healthy lung. In lung transplantation, long-term management remains limited by chronic lung allograft ...dysfunction, an umbrella term used for a heterogeneous entity ultimately associated with pathological airway and/or parenchyma remodeling.
This study assessed whether the local cross-talk between the pulmonary microbiota and host cells is a key determinant in the control of lower airway remodeling posttransplantation.
Microbiota DNA and host total RNA were isolated from 189 bronchoalveolar lavages obtained from 116 patients post lung transplantation. Expression of a set of 11 genes encoding either matrix components or factors involved in matrix synthesis or degradation (anabolic and catabolic remodeling, respectively) was quantified by real-time quantitative PCR. Microbiota composition was characterized using 16S ribosomal RNA gene sequencing and culture.
We identified 4 host gene expression profiles, among which catabolic remodeling, associated with high expression of metallopeptidase-7, -9, and -12, diverged from anabolic remodeling linked to maximal thrombospondin and platelet-derived growth factor D expression. While catabolic remodeling aligned with a microbiota dominated by proinflammatory bacteria (eg, Staphylococcus, Pseudomonas, and Corynebacterium), anabolic remodeling was linked to typical members of the healthy steady state (eg, Prevotella, Streptococcus, and Veillonella). Mechanistic assays provided direct evidence that these bacteria can impact host macrophage-fibroblast activation and matrix deposition.
Host-microbes interplay potentially determines remodeling activities in the transplanted lung, highlighting new therapeutic opportunities to ultimately improve long-term lung transplant outcome.
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Perovskite nanophotonics is a rapidly emerging field that combines research in synthesis of materials with novel properties and in photonics design strategies. Starting from early pioneering works on ...halide perovskite compounds that showed great potential across optoelectronics and photonics applications, the field is ready to blossom by combining recent advances in synthetic material design, the development of bottom-up or top-down nanostructuring approaches and new concepts in nanohophotonic engineering of light matter interaction at the nanoscale, with a chance of having real impact on current and future technologies. This roadmap is a collective outlook from pioneers in the field of perovskite nanophotonics that encompasses a number of the emerging research areas with the aim of identifying current and future challenges and highlighting the most promising research directions. It will be of interest and serve as a reference to a wide audience of physicists, chemists and engineers with interest in perovskite nanophotonics.
•Nanophotonics has emerged as the branch of science capable of connecting conventional optics with nanoscale phenomena. The key feature enabling this convergence is the ability of nano-sized photonic objects to confine light within volumes comparable or smaller than their physical sizes, far beyond the operation wavelength.•The materials of choice for nanophotonics, to manage light at the subwavelength regime, are either metals, because of their ability to support surface plasmon resonances or, with increasingly high interest, nanostructured dielectrics. The latter are mostly made of conventional semiconductors, due to their inherently high refractive index, low optical losses, active functionalities, and well-established fabrication methods.•Halide perovskites are the most recent addition to the dielectric nanophotonic platforms. Besides their well-known optoelectronic properties, cost-effectiveness, ease of processability, bandgap tunability, high-tolerance to defects, and high luminescence quantum yield, halide perovskites are well suited for a variety of nano-fabrication techniques and possess refractive indices high enough to efficiently support optical resonances when nanostructured.•The aim of this Roadmap on perovskite nanophotonics is to provide a broad view of the state-of-the-art of this emerging research field, thanks to the contributions of renowned experts, affiliated to both academic institutions and high-tech industries. The roadmap also aims to discuss the advances required to tackle emerging challenges, and to provide insights about the medium-long term perspectives offered by perovskite nanophotonic devices and systems.
We present a search for signatures of neutrino mixing of electron anti-neutrinos with additional hypothetical sterile neutrino flavors using the Double Chooz experiment. The search is based on data ...from 5 years of operation of Double Chooz, including 2 years in the two-detector configuration. The analysis is based on a profile likelihood, i.e. comparing the data to the model prediction of disappearance in a data-to-data comparison of the two respective detectors. The analysis is optimized for a model of three active and one sterile neutrino. It is sensitive in the typical mass range
5
×
10
-
3
eV
2
≲
Δ
m
41
2
≲
3
×
10
-
1
eV
2
for mixing angles down to
sin
2
2
θ
14
≳
0.02
. No significant disappearance additionally to the conventional disappearance related to
θ
13
is observed and correspondingly exclusion bounds on the sterile mixing parameter
θ
14
as a function of
Δ
m
41
2
are obtained.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The precise modeling of the de-excitation of Gd isotopes is of great interest for experimental studies of neutrinos using Gd-loaded organic liquid scintillators. The FIFRELIN code was recently used ...within the purposes of the STEREO experiment for the modeling of the Gd de-excitation after neutron capture in order to achieve a good control of the detection efficiency. In this work, we report on the recent additions in the FIFRELIN de-excitation model with the purpose of enhancing further the de-excitation description. Experimental transition intensities from the EGAF database are now included in the FIFRELIN cascades, in order to improve the description of the higher energy part of the spectrum. Furthermore, the angular correlations between
γ
rays are now implemented in FIFRELIN, to account for the relative anisotropies between them. In addition, conversion electrons are now treated more precisely in the whole spectrum range, while the subsequent emission of X rays is also accounted for. The impact of the aforementioned improvements in FIFRELIN is tested by simulating neutron captures in various positions inside the STEREO detector. A repository of up-to-date FIFRELIN simulations of the Gd isotopes is made available for the community, with the possibility of expanding for other isotopes which can be suitable for different applications.
Recent investigations showed that isoflurane can induce pharmacological preconditioning. The present study aimed to compare the potency of four different halogenated anaesthetics to induce ...preconditioning.
Anaesthetized open-chest rabbits underwent 30 min of coronary artery occlusion followed by 3 h of reperfusion. Before this, rabbits were randomized into one of five groups and underwent a treatment period consisting of either no intervention for 45 min (control; n = 10), or 30 min of 1 MAC halogenated anaesthetic inhalation followed by 15 min of washout. End-tidal concentrations of halogenated agents were 3.7% for sevoflurane (n = 11), 1.4% for halothane (n = 9), 2.0% for isoflurane (n = 11), and 8.9% for desflurane (n = 11). Area at risk and infarct size were assessed by blue dye injection and tetrazolium chloride staining.
Mean (SD) infarct size was 54 (18)% of the risk area in untreated controls and 40 (18)% in the sevoflurane group (P>0.05, ns). In contrast, mean infarct size was significantly smaller in the halothane, isoflurane, and desflurane groups: 26 (18)%, 32 (18)% and 16 (17)%, respectively (P<0.05 vs control).
Halothane, isoflurane and desflurane induced pharmacological preconditioning, whereas sevoflurane had no significant effect. In this preparation, desflurane was the most effective agent at preconditioning the myocardium against ischaemia.
A
bstract
A
θ
13
oscillation analysis based on the observed antineutrino rates at the Double Chooz far and near detectors for different reactor power conditions is presented. This approach provides a ...so far unique simultaneous determination of
θ
13
and the total background rates without relying on any assumptions on the specific background contributions. The analysis comprises 865 days of data collected in both detectors with at least one reactor in operation. The oscillation results are enhanced by the use of 24.06 days (12.74 days) of reactor-off data in the far (near) detector. The analysis considers the
ν
¯
e
interactions up to a visible energy of 8.5 MeV, using the events at higher energies to build a cosmogenic background model considering fast-neutrons interactions and
9
Li decays. The background-model-independent determination of the mixing angle yields sin
2
(2
θ
13
) = 0
.
094 ± 0
.
017, being the best-fit total background rates fully consistent with the cosmogenic background model. A second oscillation analysis is also performed constraining the total background rates to the cosmogenic background estimates. While the central value is not significantly modified due to the consistency between the reactor-off data and the background estimates, the addition of the background model reduces the uncertainty on
θ
13
to 0.015. Along with the oscillation results, the normalization of the anti-neutrino rate is measured with a precision of 0.86%, reducing the 1.43% uncertainty associated to the expectation.
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