Highlights ► VP-fibres and nerve terminals in the hippocampus of rat were studied under LM and EM. ► The fibres’ origin, distribution and synaptical relationship were investigated. ► VP fibres were ...present in all hippocampal areas in the whole septo-temporal extent. ► VP fibres made type I and II synapses onto hippocampal principal and interneurons. ► Hypothalamic SON and PVN served as the main source of the VP hippocampal innervation.
Relativistic jets are observed throughout the Universe and strongly affect their surrounding environments on a range of physical scales, from Galactic binary systems
to galaxies and clusters of ...galaxies
. All types of accreting black hole and neutron star have been observed to launch jets
, with the exception of neutron stars with strong magnetic fields
(higher than 10
gauss), leading to the conclusion that their magnetic field strength inhibits jet formation
. However, radio emission recently detected from two such objects could have a jet origin, among other possible explanations
, indicating that this long-standing idea might need to be reconsidered. But definitive observational evidence of such jets is still lacking. Here we report observations of an evolving jet launched by a strongly magnetized neutron star accreting above the theoretical maximum rate given by the Eddington limit. The radio luminosity of the jet is two orders of magnitude fainter than those seen in other neutron stars with similar X-ray luminosities
, implying an important role for the properties of the neutron star in regulating jet power. Our result also shows that the strong magnetic fields of ultra-luminous X-ray pulsars do not prevent such sources from launching jets.
The circumrotation of a submolecular fragment in either direction in a synthetic molecular structure is described. The movement of a small ring around a larger one occurs through positional ...displacements arising from biased Brownian motion that are kinetically captured and then directionally released. The sense of rotation is governed solely by the order in which a series of orthogonal chemical transformations is performed. The minimalist nature of the 2catenane flashing ratchet design permits certain mechanistic comparisons with the Smoluchowski-Feynman ratchet and pawl. Even when no work has to be done against an opposing force and no net energy is used to power the motion, a finite conversion of energy is intrinsically required for the molecular motor to undergo directional rotation. Nondirectional rotation has no such requirement.
To report the 24-month efficacy and safety of the interleukin-6 receptor antagonist tocilizumab (TCZ) for refractory uveitis-related macular edema (ME).
Data were obtained by standardized chart ...review. Patients with quiescent uveitis seen at a single tertiary referral center, for whom ME was the principal cause of reduced visual acuity.
Central foveal thickness measured by optical coherence tomography; degree of anterior and posterior chamber; inflammation (Standardization of Uveitis Nomenclature Working Group criteria); and visual acuity (Snellen and logarithm of the minimum angle of resolution) were recorded in all patients during TCZ therapy at months 1, 3, 6, 12, 18, and 24.
Sixteen eyes from 12 patients (10 women) were included. Mean age was 34.6 years. Mean duration of ME was 13.2 years. All patients achieved 24 months of follow-up and that is the census date for data collection. Before TCZ was commenced, ME was present, and all patients had been previously treated with immunosuppressive therapy and biologic agents. Uveitis diagnoses were juvenile idiopathic arthritis associated, uveitis (n = 6), birdshot chorioretinopathy (n = 2), idiopathic panuveitis (n = 2), sympathetic ophthalmia (n = 1), and ankylosing spondylitis (n = 1). Mean central foveal thickness (95%; confidence interval) was 516 ± 55 μm at baseline, improving to 274 ± 13 at Month 12 (P = 0.0004), and sustained at 274 ± 14 at Month 24 of follow-up (P = 0.00039). Mean logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.78 ± 0.18 (Snellen 20/120 ± 20/30) at baseline to 0.42 ± 0.17 (20/52 ± 20/30) at Month 12 (P = 0.0001) and 0.40 ± 0.17 (20/50 ± 20/30) at Month 24 of follow-up (P = 0.0002). Tocilizumab therapy was withdrawn in 5 patients with sustained remission at Month 12 but in all, ME relapsed between 1 and 3 months after TCZ discontinuation. Rechallenge of TCZ infusions led to recovery of uveitis control and ME resolution. Two adverse events were reported during two 4-month follow-ups: one Grade 1 neutropenia and one community-acquired pneumonia.
In this long-term study, TCZ was effective and had a comparable safety profile to published data for TCZ use in other indications, when used for the treatment of refractory uveitis-related ME.
We present observations of rapid (sub-second) optical flux variability in V404 Cyg during its 2015 June outburst. Simultaneous three-band observations with the ULTRACAM fast imager on four nights ...show steep power spectra dominated by slow variations on ∼100–1000 s time-scales. Near the peak of the outburst on June 26, a dramatic change occurs and additional, persistent sub-second optical flaring appears close in time to giant radio and X-ray flaring. The flares reach peak optical luminosities of ∼ few × 1036 erg s−1. Some are unresolved down to a time resolution of 24 ms. Whereas the fast flares are stronger in the red, the slow variations are bluer when brighter. The redder slopes, emitted power and characteristic time-scales of the fast flares can be explained as optically thin synchrotron emission from a compact jet arising on size scales ∼140–500 Gravitational radii (with a possible additional contribution by a thermal particle distribution). The origin of the slower variations is unclear. The optical continuum spectral slopes are strongly affected by dereddening uncertainties and contamination by strong Hα emission, but the variations of these slopes follow relatively stable loci as a function of flux. Cross-correlating the slow variations between the different bands shows asymmetries on all nights consistent with a small red skew (i.e. red lag). X-ray reprocessing and non-thermal emission could both contribute to these. These data reveal a complex mix of components over five decades in time-scale during the outburst.
Erythropoietin (Epo), the main erythropoiesis‐stimulating factor widely prescribed to overcome anemia, is also known nowadays for its cytoprotective action on non‐hematopoietic tissues. In this ...context, Epo showed not only its ability to cross the blood‐brain barrier, but also its expression in the brain of mammals. In clinical trials, recombinant Epo treatment has been shown to stimulate neurogenesis; improve cognition; and activate antiapoptotic, antioxidant, and anti‐inflammatory signaling pathways. These mechanisms, proposed to characterize a neuroprotective property, opened new perspectives on the Epo pharmacological potencies. However, many questions arise about a possible physiological role of Epo in the central nervous system (CNS) and the factors or environmental conditions that induce its expression. Although Epo may be considered a strong candidate to be used against neuronal damage, long‐term treatments, particularly when high Epo doses are needed, may induce thromboembolic complications associated with increases in hematocrit and blood viscosity. To avoid these adverse effects, different Epo analogs without erythropoietic activity but maintaining neuroprotection ability are currently being investigated. Carbamylated erythropoietin, as well as alternative molecules like Epo fusion proteins and partial peptides of Epo, seems to match this profile. This review will focus on the discussion of experimental evidence reported in recent years linking erythropoietin and CNS function through investigations aimed at finding benefits in the treatment of neurodegenerative diseases. In addition, it will review the proposed mechanisms for novel derivatives which may clarify and, eventually, improve the neuroprotective action of Epo.
Erythropoietin (Epo) stimulates erythrocyte production, however, its neuroprotective action is currently recognized. In fact, an important finding was the expression of Epo and its receptor in the mammalian brain. In order to avoid adverse effects caused by the administration of high doses of Epo, Epo derivatives without erythropoietic activity with neuroprotective function are being investigated. Despite the fact that there have been advances and highlights of Epo derivatives as promising candidates, there are still many unanswered questions and a long research process that opens new lines of study to reach an answer that helps in the therapy of neuronal diseases. These are discussed in the current Review.
Abstract
Recent models for the inner structures of active galactic nuclei (AGNs) advocate the presence of a radiatively accelerated dusty outflow launched from the outer regions of the accretion ...disk. Here, we present the first near-IR variable (rms) spectrum for the high-luminosity nearby AGN Mrk 876. We find that it tracks the accretion disk spectrum out to longer wavelengths than the mean spectrum, due to a reduced dust emission. The implied outer accretion disk radius is consistent with the IR results predicted by a contemporaneous optical accretion disk reverberation mapping campaign, and much larger than the self-gravity radius. The reduced flux variability of the hot dust could either be due to the presence of a secondary constant dust component in the mean spectrum or be introduced by the destructive superposition of the dust and accretion disk variability signals, or be some combination of the two. Assuming thermal equilibrium for optically thin dust, we derive the luminosity-based dust radii for different grain properties, using our measurement of the temperature. We find that in all the cases considered, the values are significantly larger than the dust response time measured by IR photometric monitoring campaigns, with the least discrepancy present relative to the result for a wavelength-independent dust emissivity law, i.e., a blackbody, which is appropriate for large grain sizes. This result can be well explained by assuming a flared disk-like structure for the hot dust.
ABSTRACT
We present a new method of modelling time-series data based on the running optimal average (ROA). By identifying the effective number of parameters for the ROA model, in terms of the shape ...and width of its window function and the times and accuracies of the data, we enable a Bayesian analysis, optimizing the ROA width, along with other model parameters, by minimizing the Bayesian information criterion (BIC) and sampling joint posterior parameter distributions using MCMC methods. For analysis of quasar light curves, our implementation of ROA modelling can measure time delays among light curves at different wavelengths or from different images of a lensed quasar and, in future work, be used to inter-calibrate light-curve data from different telescopes and estimate the shape and thus the power-density spectrum of the light curve. Our noise model implements a robust treatment of outliers and error-bar adjustments to account for additional variance or poorly quantified uncertainties. Tests with simulated data validate the parameter uncertainty estimates. We compare ROA delay measurements with results from cross-correlation and from javelin, which models light curves with a prior on the power-density spectrum. We analyse published COSMOGRAIL light curves of multilensed quasar light curves and present the resulting measurements of the inter-image time delays and detection of microlensing effects.
•Vegetation Filters are nature-based wastewater treatment systems.•Attenuation of EOCs is more significant in the first 90cm of soil.•With the exception of KET, EOC removals are larger than 90%.•The ...persistency of selected EOCs correlates with hydrophobicity and charge status.•Progression in the degradation pathway not always implies contaminant mitigation.
Vegetation filters (VFs), a type of land application system, are a robust technology based on natural treatment mechanisms for the removal of wastewater contaminants. Their capacity to attenuate emerging organic contaminants (EOCs) has not yet been evaluated. The present study reports the results of a 2-year EOC monitoring carried out using a poplar VF receiving wastewater primarily treated by an Imhoff tank. The compounds selected included analgesics, a β-adrenergic blocker, stimulants, an anticonvulsant, an anti-depressant, an anti-inflammatory, an antibiotic and analgesic and stimulant metabolites. EOCs were analysed in the Imhoff tank effluent, in the infiltrated water at a depth of 90cm and in the groundwater at a depth of 10m. The results demonstrated that EOC attenuation was more significant in the first 90cm than in the rest of the soil profile. The removal efficiency for all of the selected EOCs was higher than 90% with the exception of ketoprofen, which may pose a higher threat of groundwater contamination. The observed attenuation correlated with the hydrophobicity and charge state of the EOCs. The higher persistence of the metabolites 4-AAA and 4-FAA shows that progression in the degradation pathway does not always imply a mitigation of contamination.
ABSTRACT
In several montane forests around the world, epiphytes coexist in mats, sharing the rhizosphere and forming histosol‐type soils rich in nutrients. The role of these epiphytes in the ...formation of canopy soil and the fitness costs that epiphytes face when cohabiting in these mats are unknown.
In a lower montane cloud forest in central Veracruz, Mexico, a 2‐year factorial experiment was carried out with the presence/absence of ramets of Phlebodium areolatum (Polypodiaceae), Tillandsia kirchhoffiana, T. multicaulis and T. punctulata (Bromeliaceae). We examined (i) which epiphyte species contribute to the formation of canopy soil, (ii) the role of epiphyte composition in the soil nutrient composition, and (iii) the fitness costs faced by epiphytes when cohabiting.
Canopy soil formation highest when P. areolatum is present. Soil nutrient content does not change with epiphyte composition, is influenced by the microbiota, and P content decreases with the presence of epiphytes. The fitness costs show that the species compete, decreasing their survival and growth, but the competitive capacity differs between the species.
We conclude that P. areolatum is an ecosystem engineer that promotes the creation of canopy soil but is a poor competitor. The results coincide with the model of succession by facilitation. Canopy soil is a slow‐created component whose nutrient content does not depend on the epiphytic flora. In epiphyte mats, the dominant interactions are competitive, but there is also facilitation.
Canopy soil formation depends on one fern species, and the species compete inside the canopy soil carpets.
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