We determine the possible gravitational wave polarizations in two general classes of teleparallel gravity theories, using the metric and symmetric teleparallel geometries. For this purpose we apply ...the Newman–Penrose formalism, and find that depending on the choice of parameters, the E(2) class of the theories is one of N
2
,N
3
, III
5
, II
6
, corresponding to two to six polarizations, where all of them include the two tensor polarizations known from general relativity. We also find classes of theories apart from general relativity which yield the same polarizations.
We present an extension to the gauge-invariant formulation of the parameterized post-Newtonian (PPN) formalism, which allows its application to symmetric teleparallel gravity theories. In its ...original formulation, the gauge-invariant PPN formalism makes use of a gauge-invariant perturbative expansion of tensor fields; however, one of the fundamental gravitational field variables in symmetric teleparallel gravity theories is a flat, torsion-free connection, hence not a tensor field. Since connections transform differently from tensor fields under diffeomorphisms, we introduce here an adapted notion of gauge-invariant perturbation variables for the symmetric teleparallel connection, and show how the lowest order terms can be expressed in terms of the common PPN potentials.
The deterioration of food and feed stuffs and toxic intestinal effects due to fungal colonization and concomitant production of mycotoxins is an increasing concern. The development of fungi ...resistance to many commonly used chemical preservatives adds further alarm. Therefore, effective detoxification methods would be useful in counteracting this problem. Biotransformation/adsorption of mycotoxins by lactic acid bacteria and their metabolites is a promising approach to minimize the deleterious effects of mycotoxins. The objective of the present study was to evaluate the beneficial effects of Lactobacillus plantarum metabolites in reducing deoxynivalenol intestinal toxicity. To achieve this aim, histological, morphometrical and oxidative stress analyses were performed in the intestinal mucosa of piglets exposed to deoxynivalenol alone or associated with two strains (SN1 and SN2) of L. plantarum subsp. plantarum metabolites. Metabolites were obtained after dichloromethane (D) or ethyl acetate (A) extraction. Jejunal explants were exposed to the following treatments for 2 and 4 h a) culture medium (control group); b) deoxynivalenol (DON, 10 μM); c) L. plantarum metabolites DSN1; d) L. plantarum metabolites DSN1+DON; e) L. plantarum metabolites DSN2; f) L. plantarum metabolites DSN2+DON; g) L. plantarum metabolites ASN1; h) L. plantarum metabolites ASN1+DON; i) L. plantarum metabolites ASN2; j) L. plantarum metabolites ASN2+DON. The metabolites were incubated 1 h previously to DON challenge (one and 3 h of exposure). Histological assessment showed DON-treated explants with villi fusion and atrophy, multifocal apical necrosis and cuboid or flattened enterocytes with 2 and 4 h of exposure, while LP metabolites groups individually or associated with DON remained like control. The density of goblet cells in villi and crypts was reduced in DON explants compared to control group with 2 and 4 h of exposure; on the other hand, a significant increase in this parameter was achieved in LP metabolites groups compared to DON. Morphometric evaluation showed no difference in villi height or crypts depth in any treated explants. Overall, oxidative stress response assessments showed that explants exposed to SN1 extracted with dichloromethane and ethyl acetate, and SN2 extracted with dichloromethane reduced superoxide anion production. In conclusion, L. plantarum metabolites induced beneficial effects in intestinal mucosa, reducing the toxic effects of DON on intestinal morphology and oxidative response.
•Lactobacillus plantarum metabolites improve intestinal morphology.•L. plantarum metabolites increase goblet cells density.•L. plantarum metabolites decrease oxidative stress response.
So called geopolymers or geopolymeric binders and cements are made by means of an alkaline activation of materials reactive in this respect. Such material has to consist of a certain amount of ...silicate and aluminate phases which can be dissolved by the alkaline medium. In the consequence stable polymeric networks of alumosilicates will be formed. Metakaolins and alumosiliceous fly ashes, in particular, have by now achieved noteworthy significance. The search for alternative low cost or high available materials may lead among other things to “normal clays”. This material is widely available all over the world and may show certain reactivity after a thermal activation process. This investigation focuses on the suitability of illite/smectite clay to form a geopolymer after thermal and alkaline activation. Therefore clay containing mainly illite was thermally activated between 550 and 950
°C. The degree of dehydroxylation and the reached reactivity were followed by X-ray diffraction, NMR spectroscopy and dissolution techniques. The performance of the geopolymer binder in terms of strength as well as the phase composition was studied.
Decisions require careful weighing of the risks and benefits associated with a choice. Some people need to be offered large rewards to balance even minimal risks, whereas others take great risks in ...the hope for an only minimal benefit. We show here that risk-taking is a modifiable behavior that depends on right hemisphere prefrontal activity. We used low-frequency, repetitive transcranial magnetic stimulation to transiently disrupt left or right dorsolateral prefrontal cortex (DLPFC) function before applying a well known gambling paradigm that provides a measure of decision-making under risk. Individuals displayed significantly riskier decision-making after disruption of the right, but not the left, DLPFC. Our findings suggest that the right DLPFC plays a crucial role in the suppression of superficially seductive options. This confirms the asymmetric role of the prefrontal cortex in decision-making and reveals that this fundamental human capacity can be manipulated in normal subjects through cortical stimulation. The ability to modify risk-taking behavior may be translated into therapeutic interventions for disorders such as drug abuse or pathological gambling.
Ternary lanthanide indium oxides LnInO3 (Ln = La, Pr, Nd, Sm) were synthesized by high-temperature solid-state reaction and characterized by X-ray powder diffraction. Rietveld refinement of the ...powder patterns showed the LnInO3 materials to be orthorhombic perovskites belonging to the space group Pnma, based on almost-regular InO6 octahedra and highly distorted LnO12 polyhedra. Experimental structural data were compared with results from density functional theory (DFT) calculations employing a hybrid Hamiltonian. Valence region X-ray photoelectron and K-shell X-ray emission and absorption spectra of the LnInO3 compounds were simulated with the aid of the DFT calculations. Photoionization of lanthanide 4f orbitals gives rise to a complex final-state multiplet structure in the valence region for the 4f n compounds PrInO3, NdInO3, and SmInO3, and the overall photoemission spectral profiles were shown to be a superposition of final-state 4f n–1 terms onto the cross-section weighted partial densities of states from the other orbitals. The occupied 4f states are stabilized in moving across the series Pr–Nd–Sm. Band gaps were measured using diffuse reflectance spectroscopy. These results demonstrated that the band gap of LaInO3 is 4.32 eV, in agreement with DFT calculations. This is significantly larger than a band gap of 2.2 eV first proposed in 1967 and based on the idea that In 4d states lie above the top of the O 2p valence band. However, both DFT and X-ray spectroscopy show that In 4d is a shallow core level located well below the bottom of the valence band. Band gaps greater than 4 eV were observed for NdInO3 and SmInO3, but a lower gap of 3.6 eV for PrInO3 was shown to arise from the occupied Pr 4f states lying above the main O 2p valence band.
Objectives As stipulated in the guideline of the German Medical Association, all candidates for lung transplantation (LTx) undergo pre-transplant psychosocial evaluation for risk assessment. However, ...psychosocial aspects before transplantation are only important if they correlate with outcomes after transplantation. Methods In this prospective study, we used the Transplant Evaluation Rating Scale (TERS) to evaluate LTx candidates who presented at Hannover Medical School between 2016 and 2018 (n = 352). Clinical outcomes of interest were listing status, post-transplant outcomes (mortality, lung allograft dysfunction, hospitalizations, and renal functioning), behavioral aspects (BMI and adherence), and mental issues (levels of depression, anxiety, and quality of life (QoL)). TERS scores were divided into tertiles and the impact of the two subscale scores-'defiance" and "emotional sensitivity"-was investigated. Results Of the patients who were transplanted (n = 271) and were still alive (n = 251), 240 had already reached their 1-year assessment and were re-evaluated. BMI, adherence scores, levels of anxiety, depression, and QoL one year post-transplantation differed significantly between TERS tertiles, with higher TERS scores predicting less favorable outcomes. The TERS subscale "defiance" was predictive of BMI and adherence whereas the TERS subscale "emotional sensitivity" was predictive of symptoms of anxiety and depression, and QoL 1 year after transplantation. Conclusion Our results show that psychosocial factors as measured by the TERS score are predictors of behavioral and mental outcomes one year after LTx. The TERS allows us to identify psychosocial risk factors of interest that should be addressed before or after transplantation.
It is currently accepted that superoxide anion (O2•-) is an important mediator in pain and inflammation. The role of superoxide anion in pain and inflammation has been mainly determined indirectly by ...modulating its production and inactivation. Direct evidence using potassium superoxide (KO2), a superoxide anion donor, demonstrated that it induced thermal hyperalgesia, as assessed by the Hargreaves method. However, it remains to be determined whether KO2 is capable of inducing other inflammatory and nociceptive responses attributed to superoxide anion. Therefore, in the present study, we investigated the nociceptive and inflammatory effects of KO2. The KO2-induced inflammatory responses evaluated in mice were: mechanical hyperalgesia (electronic version of von Frey filaments), thermal hyperalgesia (hot plate), edema (caliper rule), myeloperoxidase activity (colorimetric assay), overt pain-like behaviors (flinches, time spent licking and writhing score), leukocyte recruitment, oxidative stress, and cyclooxygenase-2 mRNA expression (quantitative PCR). Administration of KO2 induced mechanical hyperalgesia, thermal hyperalgesia, paw edema, leukocyte recruitment, the writhing response, paw flinching, and paw licking in a dose-dependent manner. KO2 also induced time-dependent cyclooxygenase-2 mRNA expression in the paw skin. The nociceptive, inflammatory, and oxidative stress components of KO2-induced responses were responsive to morphine (analgesic opioid), quercetin (antioxidant flavonoid), and/or celecoxib (anti-inflammatory cyclooxygenase-2 inhibitor) treatment. In conclusion, the well-established superoxide anion donor KO2 is a valuable tool for studying the mechanisms and pharmacological susceptibilities of superoxide anion-triggered nociceptive and inflammatory responses ranging from mechanical and thermal hyperalgesia to overt pain-like behaviors, edema, and leukocyte recruitment.
Aspects of multimetric gravity Hohmann, M
Journal of physics. Conference series,
01/2014, Letnik:
532, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We present a class of gravity theories containing N ≥ 2 metric tensors and a corresponding number of standard model copies. In the Newtonian limit gravity is attractive within each standard model ...copy, but different standard model copies mutually repel each other. We discuss several aspects of these multimetric gravity theories, including cosmology, structure formation, the post-Newtonian limit and gravitational waves. The most interesting feature we find is an accelerating expansion of the universe that naturally becomes small at late times.
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