Polaritonic effects in the vibronic spectrum of molecules in an optical cavity

We present a new computational framework to describe polaritons, which treats photons and electrons on the same footing using coupled-cluster theory. As a proof of concept, we study the coupling between the first electronically excited state of carbon monoxide and an optical cavity. We focus, in particular, on how the interaction with the photonic mode changes the vibrational spectroscopic signature of the electronic state, and how this is affected when tuning the cavity frequency and the light-matter coupling strength. For this purpose, we consider different methodologies and investigate the validity of the Born-Oppenheimer approximation in such situations

Stability of loratadine tablets in Argentina

Stability of loratadine formulations can be affected when the product is exposed to high temperature and humidity. In this study, chemical and in vitro dissolution stability of loratadine (10 mg) tablets available in Argentina were assessed. Drug content and dissolution profiles were determined according to USP29, at time zero, and after 3 and 6 months of storage under ICH accelerated aging conditions (40 °C, 75 % RH). Dissolution efficiency and assay values were compared, both by mathematical and statistical methods, to assess interchangeability and stability during aging. After 180 days, most formulations evaluated showed statistically significant changes in the active ingredient and in the dissolution behaviour. Only formulation K did not meet the assay acceptance criteria.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Quality and measurement aberrations on holographic lenses

Abstract: In this paper, we have evaluated the quality of holographic lenses stored in an environmentally friendly photopolymer. Optical quality metrics has been used to test the holographic lenses. The metrics values obtained shows that the negative asymmetrical holographic lenses have the best optical quality.Work funded by Ministerio de Ciencia, Innovación y Universidades, Spain, under project PID2019-106601RB-I00; Generalitat Valenciana, Spain, under projects CDEI-GENT/2018/024, PROMETEO/2021/006, and IDIFEDER/2021/014 (co-funded by European Union through the FEDER Programme); Universidad de Alicante, Spain: Predoctoral Fellowship FPU-UA to Tomás Lloret

Relativistic EOM-CCSD for Core-Excited and Core-Ionized State Energies Based on the Four-Component Dirac–Coulomb(−Gaunt) Hamiltonian

We report an implementation of the core–valence separation approach to the four-component relativistic Hamiltonian-based equation-of-motion coupled-cluster with singles and doubles theory (CVS-EOM-CCSD) for the calculation of relativistic core-ionization potentials and core-excitation energies. With this implementation, which is capable of exploiting double group symmetry, we investigate the effects of the different CVS-EOM-CCSD variants and the use of different Hamiltonians based on the exact two-component (X2C) framework on the energies of different core-ionized and -excited states in halogen- (CH3I, HX, and X–, X = Cl–At) and xenon-containing (Xe, XeF2) species. Our results show that the X2C molecular mean-field approach [Sikkema, J.; J. Chem. Phys. 2009, 131, 124116], based on four-component Dirac–Coulomb mean-field calculations (2DCM), is capable of providing core excitations and ionization energies that are nearly indistinguishable from the reference four-component energies for up to and including fifth-row elements. We observe that two-electron integrals over the small-component basis sets lead to non-negligible contributions to core binding energies for the K and L edges for atoms such as iodine or astatine and that the approach based on Dirac–Coulomb–Gaunt mean-field calculations (2DCGM) are significantly more accurate than X2C calculations for which screened two-electron spin–orbit interactions are included via atomic mean-field integrals

Unusual morphology in the mid-Cretaceous lizard Oculudentavis

Oculudentavis khaungraae was described based on a tiny skull trapped in amber. The slender tapering rostrum with retracted narial openings, large eyes, and short vaulted braincase led to its identification as the smallest avian dinosaur on record, comparable to the smallest living hummingbirds. Despite its bird-like appearance, Oculudentavis showed several features inconsistent with its original phylogenetic placement. Here, we describe a more complete specimen that demonstrates Oculudentavis is actually a bizarre lizard of uncertain position. The new specimen is described as a new species within the genus Oculudentavis. The new interpretation and phylogenetic placement highlight a rare case of convergent evolution in skull proportions but apparently not in morphological characters. Our results re-affirm the importance of Myanmar amber in yielding unusual taxa from a forest ecosystem rarely represented in the fossil record

An assessment of different electronic structure approaches for modeling time-resolved x-ray absorption spectroscopy

We assess the performance of different protocols for simulating excited-state x-ray absorption spectra. We consider three different protocols based on equation-of-motion coupled-cluster singles and doubles, two of them combined with the maximum overlap method. The three protocols differ in the choice of a reference configuration used to compute target states. Maximum-overlap-method time-dependent density functional theory is also considered. The performance of the different approaches is illustrated using uracil, thymine, and acetylacetone as benchmark systems. The results provide guidance for selecting an electronic structure method for modeling time-resolved x-ray absorption spectroscopy

A new Early Cretaceous lizard in Myanmar amber with exceptionally preserved integument

We here report on a well-preserved juvenile lizard specimen in Albian amber (ca. 110 mya) from the Hkamti site (Myanmar). This new taxon is represented by an articulated skull and the anterior portion of the trunk, including the pectoral girdle and forelimbs. The scleral ossicles and eyelid are also visible, and the specimen exhibits pristine detail of the integument (of both head and body). In a combined molecular and morphological analysis, it was consistently recovered as a scincoid lizard (Scinciformata), as sister to Tepexisaurus + Xantusiidae. However, the phylogenetic position of the new taxon should be interpreted with caution as the holotype is an immature individual. We explored the possibility of miscoding ontogenetically variable characters by running alternative analyses in which these characters were scored as missing data for our taxon. With the exception of one tree, in which it was sister to Amphisbaenia, the specimen was recovered as a Pan-xantusiid. Moreover, we cannot rule out the possibility that it represents a separate lineage of uncertain phylogenetic position, as it is the case for many Jurassic and Cretaceous taxa. Nonetheless, this fossil offers a rare opportunity to glimpse the external appearance of one group of lizards during the Early Cretaceous

Large-scale movements of common bottlenose dolphins in the Atlantic : dolphins with an international courtyard

Wide-ranging connectivity patterns of common bottlenose dolphins (Tursiops truncatus) are generally poorly known worldwide and more so within the oceanic archipelagos of Macaronesia in the North East (NE) Atlantic. This study aimed to identify long-range movements between the archipelagos of Macaronesia that lie between 500 and 1,500 km apart, and between Madeira archipelago and the Portuguese continental shelf, through the compilation and comparison of bottlenose dolphin's photo-identification catalogues from different regions: one from Madeira (n = 363 individuals), two from different areas in the Azores (n = 495 and 176), and four from different islands of the Canary Islands (n = 182, 110, 142 and 281), summing up 1791 photographs. An additional comparison was made between the Madeira catalogue and one catalogue from Sagres, on the southwest tip of the Iberian Peninsula (n = 359). Results showed 26 individual matches, mostly between Madeira and the Canary Islands (n = 23), and between Azores and Madeira (n = 3). No matches were found between the Canary Islands and the Azores, nor between Madeira and Sagres. There were no individuals identified in all three archipelagos. The minimum time recorded between sightings in two different archipelagos (≈ 460 km apart) was 62 days. Association patterns revealed that the individuals moving between archipelagos were connected to resident, migrant and transient individuals in Madeira. The higher number of individuals that were re-sighted between Madeira and the Canary Islands can be explained by the relative proximity of these two archipelagos. This study shows the first inter-archipelago movements of bottlenose dolphins in the Macaronesia region, emphasizing the high mobility of this species and supporting the high gene flow described for oceanic dolphins inhabiting the North Atlantic. The dynamics of these long-range movements strongly denotes the need to review marine protected areas established for this species in each archipelago, calling for joint resolutions from three autonomous regions belonging to two EU countries.Partnership Program (US) and project ‘‘Cetáceos, Oceanografía y Biodiversidad de las Aguas Profundas de La Palma y El Hierro’’ funded by ‘‘Ministerio de Ciencia e Innovación’’ of the Spanish Government, grant number CETOBAPH-CGL2009-1311218 supported the work in the Canary Island. In Madeira, this study was supported by the Oceanic Observatory of Madeira through the project M1420-01-0142-FEDER-000001 and by the Portuguese Foundation for Science and Technology through the strategic project UID/MAR/04292/2020. Ana Dinis and Filipe Alves have grants funded by ARDITI— Madeira’s Regional Agency for the Development of Research, Technology and Innovation, throughout the project M1420-09- 5369- FSE- 000002, and Annalisa Sambolino is supported by the Portuguese Foundation for Science and Technology through the PhD grant number SFRH/BD/1416092018. In Azores, the MONICET platform is supported by project MEEMO (ACORES-01-0145-FEDER-000079) and Marta Tobena is supported by a PhD grant (M31a/F/0722015). There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

Efficient and stable holographic gratings stored in an environmentally friendly photopolymer

Holographic gratings stored in low-toxicity photopolymer, Biophotopol, have been analyzed to achieve stable and efficient holograms. A curing process allows the hologram stabilization, but at the same time, it could produce a diffraction efficiency (DE) reduction. Here, a detailed low-cost LED curing protocol is shown to stabilize over time 1205 l/mm transmission holograms, and at the same time, a 33% DE increment (with respect non-curing holograms) have been demonstrated. Finally, to obtain a better understanding of DE change, a theoretical fit of our experimental result, based on Kogelnik’s coupled wave theory was carried out and discussed.Ministerio de Ciencia, Innovación y Universidades, Spain, under projects FIS2017-82919-R (MINECO/AE/FEDER, UE) and FIS2015-66570-P (MINECO/FEDER); Generalitat Valenciana, Spain, under project CDEIGENT/2018/024 and GRE17-06

Efficient and stable holographic gratings stored in an environmentally friendly photopolymer

Holographic gratings stored in one of the greenest photopolymers, called Biophotopol and patented by Holography and Optical Processing group at the University of Alicante, have been analyzed to achieve stable over time and efficient holograms. A curing process usually produces a diffraction efficiency (DE) decrement. However, when a curing process is not performed, the holographic gratings are not stable and DE will decrease over time due to the diffusion of molecular components inside the photopolymer. In this work, a DE increment has been demonstrated after a curing stage (performed with an incoherent and lowcost LED lamp). A detailed curing protocol to stabilize the holograms while maintaining high DE, has been carried out in unslanted transmission gratings of 1205 l/mm. The holographic transmission reflection setup allows the possibility to evaluate the transmitted and diffracted intensity beam relation, in real time, by using a He-Ne laser (633 nm), while the gratings were recording with an Argon laser (488 nm). It has been demonstrated more than a 30% DE increment after a curing process when a maximum DE in the recording stage had not been still achieved. However, in the singular case that a maximum DE in the recording stage has been already obtained, a curing stage process could produce overmodulation effects, and therefore, a DE decrement. In conclusion, a maximum DE is obtained in curing and stable hologram gratings (recording them with proper radiant exposures) over an environmentally compatible photopolymer.This work was supported by the “Ministerio de Ciencia, Innovación y Universidades” (Spain) under projects FIS2017-82919-R (MINECO/AE/FEDER, UE) and FIS2015-66570-P (MINECO/FEDER) ang by the University of Alicante under project GRE17-06. M.M-V. acknowledge the financial support by the "Generalitat Valenciana” (Spain) under grant CDEIGENT/2018/024