212 research outputs found
Equation of Motion for the Solvent Polarization Apparent Charges in the Polarizable Continuum Model: Application to Time-Dependent CI
The dynamics of the electrons for a molecule in solution is coupled to the
dynamics of its polarizable environment, i.e., the solvent. To theoretically
investigate such electronic dynamics, we have recently developed equations of
motion (EOM) for the apparent solvent polarization charges that generate the
reaction field in the Polarizable Continuum Model (PCM) for solvation and we
have coupled them to a real-time time-dependent density functional theory (RT
TDDFT) description of the solute [Corni et al. J. Phys. Chem. A 119, 5405
(2014)]. Here we present an extension of the EOM-PCM approach to a
Time-Dependent Configuration Interaction (TD CI) description of the solute
dynamics, which is free from the qualitative artifacts of RT TDDFT in the
adiabatic approximation. As tests of the developed approach, we investigate the
solvent Debye relaxation after an electronic excitation of the solute obtained
either by a pulse of light or by assuming the idealized sudden promotion
to the excited state. Moreover, we present EOM for the Onsager solvation model
and we compare the results with PCM. The developed approach provides
qualitatively correct real-time evolutions and is promising as a general tool
to investigate the electron dynamics elicited by external electromagnetic
fields for molecules in solution.Comment: This is the final peer-reviewed manuscript accepted for publication
in The Journal of Chemical Physics. Copyright by AIP, the final published
version can be found at
http://scitation.aip.org/content/aip/journal/jcp/146/6/10.1063/1.497562
Correlation Redistribution by Causal Horizons
The Minkowski vacuum , which for an inertial observer is devoid
of particles, is treated as a thermal bath by Rindler observers living in a
single Rindler wedge, as a result of the discrepancy in the definition of
positive frequency between the two classes of observers and a strong
entanglement between degrees of freedom in the left and right Rindler wedges.
We revisit, in the context of a free scalar Klein-Gordon field, the problem of
quantification of the correlations between an inertial observer Alice and
left/right Rindler observes Rob/AntiRob. We emphasize the analysis of
informational quantities, like the locally accessible and locally inaccessible
information, and a closely associated entanglement measure, the entanglement of
formation. We conclude that, with respect to the correlation structure probed
by inertial observers alone, the introduction of a Rindler observer gives rise
to a correlation redistribution which can be quantified by the entanglement of
formation.Comment: 9 pages, 7 figure
Real-Time Description of the Electronic Dynamics for a Molecule close to a Plasmonic Nanoparticle
The optical properties of molecules close to plasmonic nanostructures greatly
differ from their isolated molecule counterparts. To theoretically investigate
such systems in a Quantum Chemistry perspective, one has to take into account
that the plasmonic nanostructure (e.g., a metal nanoparticle - NP) is often too
large to be treated atomistically. Therefore, a multiscale description, where
the molecule is treated by an ab initio approach and the metal NP by a lower
level description, is needed. Here we present an extension of one such
multiscale model [Corni, S.; Tomasi, J. {\it J. Chem. Phys.} {\bf 2001}, {\it
114}, 3739] originally inspired by the Polarizable Continuum Model, to a
real-time description of the electronic dynamics of the molecule and of the NP.
In particular, we adopt a Time-Dependent Configuration Interaction (TD CI)
approach for the molecule, the metal NP is described as a continuous dielectric
of complex shape characterized by a Drude-Lorentz dielectric function and the
molecule- NP electromagnetic coupling is treated by an equation-of-motion (EOM)
extension of the quasi-static Boundary Element Method (BEM). The model includes
the effects of both the mutual molecule- NP time-dependent polarization and the
modification of the probing electromagnetic field due to the plasmonic
resonances of the NP. Finally, such an approach is applied to the investigation
of the light absorption of a model chromophore, LiCN, in the presence of a
metal NP of complex shape.Comment: This is the final peer-reviewed manuscript accepted for publication
of an open access article published under an ACS AuthorChoice License, which
permits copying and redistribution of the article or any adaptations for
non-commercial purposes. Link to the original article:
http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b1108
Adenoidal Disease and Chronic Rhinosinusitis in Children-Is there a Link?
Adenoid hypertrophy (AH) is an extremely common condition in the pediatric and adolescent populations that can lead to various medical conditions, including acute rhinosusitis, with a percentage of these progressing to chronic rhinosinusitis (CRS). The relationship between AH and pediatric CRS has been extensively studied over the past few years and clinical consensus on the treatment has now been reached, allowing this treatment to become the preferred clinical practice. The purpose of this study is to review existing literature and data on the relationship between AH and CRS and the options for treatment. A systematic literature review was performed using a search line for "(Adenoiditis or Adenoid Hypertrophy) and Sinusitis and (Pediatric or Children)". At the end of the evaluation, 36 complete texts were analyzed, 17 of which were considered eligible for the final study, dating from 1997 to 2018. The total population of children assessed in the various studies was of 2371. The studies were categorized as surgical-observational, microbiological, genetic-immunological, and radiological. The analysis of the studies confirms the relationship between AH and CRS and supports the existing consensus on medical and surgical therapy. Furthermore, these studies underline the necessity to adapt medical and surgical treatment considering age, comorbidities including asthma and, if present, the Computed Tomography (CT) score
Maxillary sinus elevation in conjunction with transnasal endoscopic treatment of rhino-sinusal pathoses: preliminary results on 10 consecutively treated patients
A one-step surgical procedure is presented, including maxillary sinus floor elevation in association with functional endoscopic sinus surgery to remove rhino-sinusal malformations or pathoses that might contraindicate sinus floor elevation. Over a 2-year period, 10 patients requiring a sinus floor augmentation procedure to restore the missing dentition with endosseous implants, but presenting with local and reversible rhinologic contraindications to the augmentation procedure were consecutively treated with a surgical approach that included simultaneously functional endoscopic sinus surgery and a sinus floor elevation procedure through an intra-oral approach. Then 4-6 months after this procedure, oral implants were inserted and after a further waiting period, ranging from 3 to 6 months, patients were restored with prostheses and followed for 1 to 3 years after the completion of prosthetic restoration. In all 10 patients, complete recovery of para-nasal sinuses function was demonstrated and occurred in all cases within one month. All cases showed good integration and consolidation of the graft material used for maxillary sinus floor augmentation. None of the implants placed were lost during the follow-up period after completion of prosthetic loading. In conclusion, despite the limits of this study (which included only 10 patients), the combination of maxillary sinus augmentation procedures and functional endoscopic sinus surgery, to treat local contraindications to sinus augmentation has proven to be both effective and safe and has allowed the patient to avoid a second surgical procedure and a longer waiting period before final prosthetic rehabilitation. No sinusal complications related to sinus floor augmentation were encountered and the survival rate of implants placed in the augmented areas was consistent with those reported in cases of sinus floor augmentation performed in patients presenting with a healthy rhino-sinusal system
Orbital medial wall fractures: Purely endoscopic endonasal repair with polyethylene implants
Our technique couples the stronger support granted by non-resorbable materials and the minimal invasiveness of the endoscopic approach without the need for long-term nasal packing
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