5,202 research outputs found
Tamara Kotevska, Ljubomir Stefanov, Honeyland, North Macedonia, 2019, 87’
Review of Tamara Kotevska, Ljubomir Stefanov, Honeyland, North Macedonia, 2019, 87’.Recensione di Tamara Kotevska, Ljubomir Stefanov, Honeyland, North Macedonia, 2019, 87’
16th RAI Film Festival 2019 | Bristol (UK), 27-30 March 2019
Review of the 16th RAI Film Festival 2019 | Bristol (UK), 27-30 March 2019.Recensione del 16th RAI Film Festival 2019 | Bristol (UK), 27-30 March 2019
Human mobility networks and persistence of rapidly mutating pathogens
Rapidly mutating pathogens may be able to persist in the population and reach
an endemic equilibrium by escaping hosts' acquired immunity. For such diseases,
multiple biological, environmental and population-level mechanisms determine
the dynamics of the outbreak, including pathogen's epidemiological traits (e.g.
transmissibility, infectious period and duration of immunity), seasonality,
interaction with other circulating strains and hosts' mixing and spatial
fragmentation. Here, we study a susceptible-infected-recovered-susceptible
model on a metapopulation where individuals are distributed in subpopulations
connected via a network of mobility flows. Through extensive numerical
simulations, we explore the phase space of pathogen's persistence and map the
dynamical regimes of the pathogen following emergence. Our results show that
spatial fragmentation and mobility play a key role in the persistence of the
disease whose maximum is reached at intermediate mobility values. We describe
the occurrence of different phenomena including local extinction and emergence
of epidemic waves, and assess the conditions for large scale spreading.
Findings are highlighted in reference to previous works and to real scenarios.
Our work uncovers the crucial role of hosts' mobility on the ecological
dynamics of rapidly mutating pathogens, opening the path for further studies on
disease ecology in the presence of a complex and heterogeneous environment.Comment: 29 pages, 7 figures. Submitted for publicatio
The R18 polyarginine peptide is more effective than the TAT-NR2B9c (NA-1) peptide when administered 60 minutes after permanent middle cerebral artery occlusion in the rat
We examined the dose responsiveness of polyarginine R18 (100, 300, and 1000 nmol/kg) when administered 60 minutes after permanent middle cerebral artery occlusion (MCAO).The TAT-NR2B9c peptide, which is known to be neuroprotective in rodent and nonhuman primate stroke models, served as a positive control. At 24 hours afterMCAO, there was reduced total infarct volume in R18 treated animals at all doses, but this reduction only reached statistical significance at doses of 100 and 1000 nmol/kg. The TAT-NR2B9c peptide reduced infarct volume at doses of 300 and 1000 nmol/kg, but not to a statistically significant extent, while the 100 nmol/kg dose was ineffective.The reduction in infarct volume with R18 and TAT-NR2B9c peptide treatments was mirrored by improvements in one or more functional outcomes (namely, neurological score, adhesive tape removal, and rota-rod), but not to a statistically significant extent. These findings further confirm the neuroprotective properties of polyarginine peptides and for R18 extend its therapeutic time window and dose range, as well as demonstrating its greater efficacy compared to TAT-NR2B9c in a severe stroke model.The superior neuroprotective efficacy of R18 over TAT-NR2B9c highlights the potential of this polyarginine peptide as a lead candidate for studies in human stroke
Experimental and Computational Study of the New Gaseous Molecules OMnF and OMnF[Sub 2]
The new gaseous species OMnF and OMnF2 were identified and studied by high-temperature Knudsen Cell Mass Spectrometry. Their thermochemical atomization energies were derived through the study of several all-gas equilibria in the temperature range 1735–1913 K. FTIR matrix isolation experiments together with ab initio and density functional calculations were performed to determine the molecular parameters, bond distances, and vibrational frequencies of OMnF(g) and OMnF2(g) . The results allowed us to evaluate a set of thermal functions for the new species that were used in the evaluation of the equilibrium data. The proposed atomization energies and enthalpies of formation are DaH0 + (OMnF,g)5(90365) kJ mol21, DfH298.15 + (OMnF,g)5(229765) kJ mol21, and DaH0 + (OMnF2 ,g)5(1470670) kJ mol21, DfH298.15 + (OMnF2 ,g)5(2789670) kJ mol21
Loop bounds on non-standard neutrino interactions
We reconsider the bounds on non-standard neutrino interactions with matter
which can be derived by constraining the four-charged-lepton operators induced
at the loop level. We find that these bounds are model dependent. Naturalness
arguments can lead to much stronger constraints than those presented in
previous studies, while no completely model-independent bounds can be derived.
We will illustrate how large loop-contributions to four-charged-lepton
operators are induced within a particular model that realizes gauge invariant
non-standard interactions and discuss conditions to avoid these bounds. These
considerations mainly affect the constraint on the
non-standard coupling strength \eps_{e\mu}, which is lost. The only
model-independent constraints that can be derived are .
However, significant cancellations are required in order to saturate this
bound.Comment: Minor changes, version to be published in JHEP. 17 pages, 3 Axodraw
figures, REVTeX
Legacy of wood charcoal production on subalpine forest structure and species composition
Land-use legacy on forest dynamics at both stand and landscape scale can last for centuries, affecting forest structure and species composition. We aimed to disentangle the history of the charcoal production legacies that historically shaped Mont Avic Natural Park (Aosta Valley, Italy) forests by integrating LiDAR, GIS, anthracological, and field data at the landscape scale. We adopted different geostatistical tools to relate geographic layers from various data sources. The overexploitation due to intensive charcoal production to fuel mining activities shaped the current forests by homogenising their structure and species composition into dense and young stands with a reduction in late seral species such as Norway spruce (Picea abies) and an increase in pioneer species such as Mountain pine (Pinus uncinata). The multidisciplinary and multi-scale framework adopted in this study stresses the role of historical landscape ecology in evaluating ecosystem resilience to past anthropogenic disturbances. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13280-022-01750-y
Poly-arginine peptides reduce infarct volume in a permanent middle cerebral artery rat stroke model
Background: We recently reported that poly-arginine peptides have neuroprotective properties both in vitro and in vivo. In cultured cortical neurons exposed to glutamic acid excitotoxicity, we demonstrated that neuroprotective potency increases with polymer length plateauing at R15 to R18 (R = arginine resides). In an in vivo study in rats, we also demonstrated that R9D (R9 peptide synthesised with D-isoform amino acids) administered intravenously at a dose of 1000 nmol/kg 30 min after permanent middle cerebral artery occlusion (MCAO) reduces infarct volume. Based on these positive in vitro and in vivo findings, we decided to examine the neuroprotective efficacy of the L-isoform poly-arginine peptides, R12, R15 and R18 when administered at a dose of 1000 nmol/kg 30 min after permanent MCAO in the rat.
Results: At 24 h post-MCAO, there was reduced total infarct volume for R12 (12.8 % reduction) and R18 (20.5 % reduction), but this reduction only reached statistical significance for R18. Brain slice analysis revealed significantly reduced injury in coronal slices 4 and 5 for R18, and slice 5 for R12. The R15 peptide had no effect on infarct volume. Peptide treatment did not reveal any statistical significant improvement in functional outcomes.
Conclusion: While these findings confirm the in vivo neuroprotective properties of poly-arginine peptides, additional dose studies are required particularly in less severe transient MCAO models so as to further assess the potential of these agents as a stroke therapy
Spectroscopic Characterization of the Ground and Low-Lying Electronic States of Ga2N via Anion Photoelectron Spectroscopy.
Anion photoelectron spectra of Ga2N− were measured at photodetachment wavelengths of 416nm(2.978eV), 355nm(3.493eV), and 266nm(4.661eV). Both field-free time-of-flight and velocity-map imaging methods were used to collect the data. The field-free time-of-flight data provided better resolution of the features, while the velocity-map-imaging data provided more accurate anisotropy parameters for the peaks. Transitions from the ground electronic state of the anion to two electronic states of the neutral were observed and analyzed with the aid of electronic structure calculations and Franck-Condon simulations. The ground-state band was assigned to a transition between linear ground states of Ga2N−(XΣg+1) and Ga2N(XΣu+2), yielding the electron affinity of Ga2N, 2.506±0.008eV. Vibrationally resolved features in the ground-state band were assigned to symmetric and antisymmetric stretch modes of Ga2N, with the latter allowed by vibronic coupling to an excited electronic state. The energy of the observed excited neutral state agrees with that calculated for the AΠu2 state, but the congested nature of this band in the photoelectron spectrum is more consistent with a transition to a bent neutral state
RooHammerModel: interfacing the HAMMER software tool with the HistFactory package
Recent -physics results have sparkled great interest in the search for
beyond-the-Standard-Model (BSM) physics in transitions.
The need to analyse in a consistent manner big datasets for these searches,
using high-statistics Monte-Carlo (MC) samples, led to the development of
HAMMER, a software tool which enables to perform a fast morphing of MC-derived
templates to include BSM effects and/or alternative parameterisations of
long-distance effects, avoiding the need to re-generate simulated samples. This
note describes the development of RooHammerModel, an interface between this
tool and the commonly-used data-fitting framework HistFactory. The code is
written in C++ and admits an alternative usage in standalone RooFit analyses.
In this document, the structure and functionality of the user interface are
explained. Information of a public repository where it can be accessed is
provided, as well as validation and performance studies of the interface. The
methods developed in the construction of RooHammerModel can provide specific
information for alternative future attempts to interface HAMMER with other
data-fitting frameworks
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