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1.
Nature ; 621(7980): 716-722, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37758891

RESUMEN

Einstein's general theory of relativity from 19151 remains the most successful description of gravitation. From the 1919 solar eclipse2 to the observation of gravitational waves3, the theory has passed many crucial experimental tests. However, the evolving concepts of dark matter and dark energy illustrate that there is much to be learned about the gravitating content of the universe. Singularities in the general theory of relativity and the lack of a quantum theory of gravity suggest that our picture is incomplete. It is thus prudent to explore gravity in exotic physical systems. Antimatter was unknown to Einstein in 1915. Dirac's theory4 appeared in 1928; the positron was observed5 in 1932. There has since been much speculation about gravity and antimatter. The theoretical consensus is that any laboratory mass must be attracted6 by the Earth, although some authors have considered the cosmological consequences if antimatter should be repelled by matter7-10. In the general theory of relativity, the weak equivalence principle (WEP) requires that all masses react identically to gravity, independent of their internal structure. Here we show that antihydrogen atoms, released from magnetic confinement in the ALPHA-g apparatus, behave in a way consistent with gravitational attraction to the Earth. Repulsive 'antigravity' is ruled out in this case. This experiment paves the way for precision studies of the magnitude of the gravitational acceleration between anti-atoms and the Earth to test the WEP.

2.
J Comput Chem ; 45(13): 995-1001, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38206899

RESUMEN

The effective calculation of static nonlinear optical properties requires a considerably high accuracy at a reasonable computational cost, to tackle challenging organic and inorganic systems acting as precursors and/or active layers of materials in (nano-)devices. That trade-off implies to obtain very accurate electronic energies in the presence of externally applied electric fields to consequently obtain static polarizabilities ( α i j ) and hyper-polarizabilities ( ß i j k and γ i j k l ). Density functional theory is known to provide an excellent compromise between accuracy and computational cost, which is however largely impeded for these properties without introducing range-separation techniques. We thus explore here the ability of a modern (double-hybrid and range-separated) Range-Separated eXchange Quadratic Integrand Double-Hybrid exchange-correlation functional to compete in accuracy with more costly and/or tuned methods, thanks to its robust and parameter-free nature.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38741198

RESUMEN

OBJECTIVES: The aims of this study were to investigate the prevalence of dose reduction in patients with SLE treated with belimumab (BEL) in Spain, analyze treatment modalities, and determine impact on control of disease activity. METHODS: Retrospective longitudinal and multicentre study of SLE patients treated with BEL. Data on disease activity, treatments and outcomes were recorded before and after reduction (6-12 months), and they were compared. RESULTS: A total of 324 patients were included. The dose was reduced in 29 patients (8.9%). The dosing interval was increased in 9 patients receiving subcutaneous BEL and in 6 patients receiving intravenous BEL. The dose per administration was reduced in 16 patients.Pre-reduction status was remission (2021 DORIS) in 15/26 patients (57.7%) and LLDAS in 23/26 patients (88.5%). After reduction, 2/24 patients (8.3%) and 3/22 patients (13.6%) lost remission at 6 months and 12 months, respectively (not statistically significant [NS]). As for LLDAS, 2/23 patients (8.7%) and 2/21 patients (9.5%) lost their status at 6 and 12 months, respectively (NS). Significantly fewer patients were taking glucocorticoids (GCs) at their 12-month visit, although the median dose of GCs was higher at the 12-month visit (5 [0.62-8.75] vs 2.5 [0-5] at baseline). CONCLUSION: Doses of BEL can be reduced with no relevant changes in disease activity-at least in the short term-in a significant percentage of patients, and most maintain the reduced dose. However, increased clinical or serologic activity may be observed in some patients. Consequently, tighter post-reduction follow-up is advisable.

4.
Environ Res ; 242: 117501, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37996003

RESUMEN

High amounts of phosphorus (P) in rivers come mainly from two sources: fertilizers washed off from agricultural and urban areas by runoff water (non-point sources) and urban and industrial development which are translated in P discharges from wastewater treatment plants (WWTP). This work analyses the content of P in water for nearly 40 years inquiring into the origin of the sources, based on the hypothesis of runoff generation from the detection of river streamflow increases during the P contribution episode and the previous precipitation. For this purpose, the Guadaira River, which is located in the South of Spain and has a drainage surface of 1524 km2, was selected. In this watershed agricultural land use converges with numerous human activities resulting in high pressures on water quality. We found 40% of the P contribution episodes found seem to come from the runoff generated after the heaviest rainfall events, which normally occur between November and May. The remaining 60% of the P contribution episodes were found to be linked to point sources, which become more relevant from June to September, reaching the highest concentration values (6-17 mg/L). The results highlight that the target phosphate concentration value of 0.34 mg PO4/L imposed by the national legislation for a good state following the Water Framework Directive 2000/60/EC is exceeded by 96% of the measurements during the period from 1981 to 2022. On a monthly basis, PO4 loads showed a linear relationship with river streamflow (R2 = 0.94). However, on field measurements scale, a potential relationship between both variables was found, which changed according to the improvement in the wastewater treatment and facilities for 1982-1994, 1995-2017 and 2018-2022. In these three periods, different significant decreasing trends of the P content were found, mainly marked by the setup of each individual WWTP.


Asunto(s)
Fósforo , Contaminantes Químicos del Agua , Humanos , Fósforo/análisis , Monitoreo del Ambiente/métodos , Estaciones del Año , Calidad del Agua , Fosfatos/análisis , Ríos , Contaminantes Químicos del Agua/análisis
5.
BMC Public Health ; 24(1): 1692, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918744

RESUMEN

AIMS: This study sought to develop and assess an exploratory model of how demographic and psychosocial attributes, and drug use or acquisition behaviors interact to affect opioid-involved overdoses. DESIGN: We conducted exploratory and confirmatory factor analysis (EFA/CFA) to identify a factor structure for ten drug acquisition and use behaviors. We then evaluated alternative structural equation models incorporating the identified factors, adding demographic and psychosocial attributes as predictors of past-year opioid overdose. SETTING AND PARTICIPANTS: We used interview data collected for two studies recruiting opioid-misusing participants receiving services from a community-based syringe services program. The first investigated current attitudes toward drug-checking (N = 150). The second was an RCT assessing a telehealth versus in-person medical appointment for opioid use disorder treatment referral (N = 270). MEASUREMENTS: Demographics included gender, age, race/ethnicity, education, and socioeconomic status. Psychosocial measures were homelessness, psychological distress, and trauma. Self-reported drug-related risk behaviors included using alone, having a new supplier, using opioids with benzodiazepines/alcohol, and preferring fentanyl. Past-year opioid-involved overdoses were dichotomized into experiencing none or any. FINDINGS: The EFA/CFA revealed a two-factor structure with one factor reflecting drug acquisition and the second drug use behaviors. The selected model (CFI = .984, TLI = .981, RMSEA = .024) accounted for 13.1% of overdose probability variance. A latent variable representing psychosocial attributes was indirectly associated with an increase in past-year overdose probability (ß = .234, p = .001), as mediated by the EFA/CFA identified latent variables: drug acquisition (ß = .683, p < .001) and drug use (ß = .567, p = .001). Drug use behaviors (ß = .287, p = .04) but not drug acquisition (ß = .105, p = .461) also had a significant, positive direct effect on past-year overdose. No demographic attributes were significant direct or indirect overdose predictors. CONCLUSIONS: Psychosocial attributes, particularly homelessness, increase the probability of an overdose through associations with risky drug acquisition and drug-using behaviors. Further research is needed to replicate these findings with populations at high-risk of an opioid-related overdose to assess generalizability and refine the metrics used to assess psychosocial characteristics.


Asunto(s)
Trastornos Relacionados con Opioides , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/psicología , Sobredosis de Opiáceos/epidemiología , Análisis Factorial , Asunción de Riesgos , Sobredosis de Droga/psicología , Sobredosis de Droga/epidemiología , Adulto Joven
6.
J Esthet Restor Dent ; 36(2): 363-372, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37594747

RESUMEN

OBJECTIVE: To evaluate root coverage (RC) in deep single antero-mandibular RT2 and RT3 gingival recessions (GR) and to investigate the influence of several factors in RC. MATERIALS AND METHODS: Fifteen single antero-mandibular GR with a minimum depth of 3 mm were consecutively treated with a new one-stage technique (laterally positioned flap with a tunnel access and a connective tissue graft). At baseline and at 12-month follow-up, the percentage of mean root coverage (%MRC), the recession reduction (RecRed), complete root coverage (CRC) and the gain of keratinized tissue width (KTW) were assessed. Descriptive, intergroup comparative and correlation analyses were performed. RESULTS: At 12 months, a %MRC of 77.29 ± 21.48% with a mean RecRed of 4.10 ± 1.51 mm was achieved. The %MRC was 84.71 ± 21.08% in RT2, and 62.43 ± 14.17% in RT3. The mean gain of KTW was 2.10 ± 0.89 mm, with a mean gain of 2.0 ± 1.03 mm for RT2 and 2.3 ± 0.57 mm for RT3. CRC was observed in six cases, all of them being RT2. A positive association was found between the %MRC and the initial position of the tooth and of both papillae. CONCLUSIONS: This technique might be a valuable approach for the treatment of deep single antero-mandibular RT2 and RT3 recessions, even in malpositioned teeth. CLINICAL SIGNIFICANCE: A combination of different surgical techniques could provide greater vascularization to the CTG especially in malpositioned teeth in sextant V with a large avascular area to be covered.


Asunto(s)
Recesión Gingival , Humanos , Recesión Gingival/cirugía , Encía/cirugía , Resultado del Tratamiento , Raíz del Diente , Colgajos Quirúrgicos/cirugía
7.
Phys Chem Chem Phys ; 25(39): 26417-26428, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37522306

RESUMEN

In this work, we focus on the understanding of the driving force behind the S1-T1 excited-state energy inversion (which would thus violate Hund's rule, making the S1 state lower in energy than the T1 state) of two non-benzenoid non-alternant hydrocarbons, composed of odd-membered rings. The molecules considered here have identical chemical composition but different atomic configuration in space. The delicate interplay between structural and electronic factors that might induce inversion and its energy extension, only by a few meV, is systematically investigated here by state-of-the-art calculations. Qualitative and quantitative accurate predictions are obtained employing post-HF methods, thanks to the balanced and careful inclusion of electron correlation effects. The obtained results might guide and rationalize new searches for molecules violating Hund's rule, concomitantly demonstrating the importance of key contributions from the theoretical method of choice.

8.
Phys Chem Chem Phys ; 25(16): 11697-11706, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37057462

RESUMEN

We theoretically study and characterize a set of rhombus-shaped nanographenes of increasing size, or n-rhombenes, where n = 2-6, displaying zigzag edges leading to an enhancement of the (poly)radicaloid nature and the appearance of intrinsic magnetism as a function of n. Due to that system-dependent radicaloid nature, we employ spin-flip methods able to capture the challenging physics of the problem, thus providing accurate energy differences between high- and low-spin solutions. The theoretical predictions agree with the experimentally available magnetic exchange coupling for the recently synthesized 5-rhombene, as well as with the size at which the transition from a closed-shell to an open-shell ground-state solution occurs. We also investigate if standard DFT methods are able to reproduce the trend disclosed by spin-flip methods and if the results are highly dependent on the functional choice and/or the intrinsic spin contamination.

9.
J Chem Phys ; 158(4): 044105, 2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36725511

RESUMEN

A family of non-empirical double-hybrid (DH) density functionals, such as Perdew-Burke-Ernzerhof (PBE)0-DH, PBE-QIDH, and their range-separated exchange (RSX) versions RSX-0DH and RSX-QIDH, all using Perdew-Burke-Ernzerhof(PBE) exchange and correlationfunctionals, is applied here to calculate the excitation energies for increasingly longer linear and cyclic acenes as part of their intense benchmarking for excited states of all types. The energies for the two lowest-lying singlet 1La and 1Lb states of linear oligoacenes as well as the triplet 3La and 3Lb states, are calculated and compared with experimental results. These functionals clearly outperform the results obtained from hybrid functionals and favorably compare with other double-hybrid expressions also tested here, such as B2-PLYP, B2GP-PLYP, ωB2-PLYP, and ωB2GP-PLYP. The study is complemented by the computation of adiabatic S0-T1 singlet-triplet energy difference for linear acenes as well as the extension of the study to strained cyclic oligomers, showing how the family of non-empirical expressions robustly leads to competitive results.

10.
J Chem Phys ; 159(14)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37811824

RESUMEN

We update the Quadratic Integrand Double-Hybrid (QIDH) model [J. Chem. Phys. 141, 031101 (2014)] by incorporating the nonempirical restored-regularized Strongly Constrained and Appropriately Normed (r2SCAN) meta-generalized gradient approximation exchange-correlation functional, thus devising a robust density functional approximation free of any empirical parameter and incorporating all the constraints so far known for the exchange-correlation kernel. We assessed the new r2SCAN-QIDH expression on the GMTKN55 database and further extend its application to various types of non-covalent interactions (e.g., S66 × 8, O24 × 5). The assessment done shows that the model becomes very competitive in accuracy with respect to parent exchange-correlation functionals of any type, but without relying on any fitted parameter or numerical training.

11.
Harm Reduct J ; 20(1): 87, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37420196

RESUMEN

BACKGROUND: The opioid epidemic continues to be associated with high numbers of fatalities in the USA and other countries, driven mainly by the inclusion of potent synthetic opioids in street drugs. Drug checking by means of various technologies is being increasingly implemented as a harm reduction strategy to inform users about constituent drugs in their street samples. We assessed how valued drug checking services (DCS) would be for opioid street drug users given the ubiquity of fentanyl and related analogs in the drug supply, the information they would most value from drug checking, and compared expected versus actual constituent drugs in collected samples. METHODS: A convenience sample of opioid street drug users (N = 118) was recruited from two syringe service exchange programs in Chicago between 2021 and 2022. We administered brief surveys asking about overdose history, whether fentanyl was their preferred opioid, and interest in DCS. We also collected drug samples and asked participants what drug(s) they expected were in the sample. Provided samples were analyzed using LC-MS technology and the results compared to their expected drugs. RESULTS: Participants reported an average of 4.4 lifetime overdoses (SD = 4.8, range = 0-20) and 1.1 (SD = 1.8, range = 0-10) past-year overdoses. A majority (92.1%) believed they had recently used drugs containing fentanyl whether intentionally or unintentionally. Opinions about the desirability of fentanyl were mixed with 56.1% indicating they did not and 38.0% indicating they did prefer fentanyl over other opioids, mainly heroin. Attitudes toward DCS indicated a general but not uniform receptiveness with a majority indicating interest in DCS though sizeable minorities believed DCS was "too much trouble" (25.2%) or there was "no point" in testing (35.4%). Participants were especially inaccurate identifying common cutting agents and potentiating drugs such as diphenhydramine in their samples (sensitivity = .17). CONCLUSIONS: Results affirmed street drug users remain interested in using DCS to monitor their drugs and such services should be more widely available. Advanced checking technologies that provide information on the relative quantities and the different drugs present in a given sample available at point-of-care, would be most valuable but remain challenging to implement.


Asunto(s)
Sobredosis de Droga , Consumidores de Drogas , Drogas Ilícitas , Humanos , Analgésicos Opioides , Fentanilo , Heroína , Sobredosis de Droga/prevención & control , Sobredosis de Droga/epidemiología
12.
Prep Biochem Biotechnol ; 53(6): 591-598, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36121058

RESUMEN

During the last few years, an important element in the improvement of the molecular biology techniques has been the necessity for availability of high quality and functionality DNA. Several DNA extraction procedures with different results in both performance and quality, have been proposed. In this study our objective was to determine the most reliable extraction method that balances DNA quantity, and to assess the sample quantification of the fluorometric DNA quantification methods. For this, blood extracted by venopunction from 20 healthy volunteers was used to obtain DNA from buffy coat, and 4 commercial DNA extraction kits were assessed as well as two fluorometric DNA quantification methods with protocols of different complexity. Results suggest that manual methods achieve higher quality and larger yields of DNA. DNA purity obtained with the 4 extraction kits evaluated through the 260/280 and 260/230 ratio showed that the Qiacube kit fulfilled the criteria established in this work, followed very close by the Flexigene kit. On the other hand, the fluorometric DNA methods used in the samples quantification showed a higher variability when using QuantiFlour method, obtaining better results probably due to the simplicity of this protocol.


Asunto(s)
Capa Leucocitaria de la Sangre , ADN , Humanos , ADN/aislamiento & purificación
13.
J Helminthol ; 97: e35, 2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37070390

RESUMEN

Members of the genus Strigea Abildgaard, 1790 are endoparasites of birds distributed worldwide. Adults of an undescribed species of the genus Strigea were collected from the intestines of two hawk species (Rupornis magnirostris and Accipiter coperii). Other species identified as Parastrigea macrobursa that were described in Argentina were also recovered from two hawk species (Buteogallus urubitinga and Buteogallus anthracinus) in three localities along the coasts of Mexico. Specimens of the two species were sequenced for three molecular markers, the internal transcribed spacers locus (ITS1-5.8S rDNA- ITS2) and the domains D1-D3 from the large subunit from nuclear ribosomal DNA and the cytochrome c oxidase subunit 1 from mitochondrial DNA. The newly sequenced specimens were aligned with other strigeids sequences downloaded from GenBank. Maximum likelihood and Bayesian analyses inferred with each molecular marker revealed that our specimens of Strigea sp. formed an independent lineage, which is recognized herein as a new species, Strigea magnirostris n. sp., representing the first species in Mexico and the 16th in the Neotropical region. Morphologically, the new species is distinguished from other congeneric species from the Americas by having an oral sucker with several papillae around it, well-developed pseudosuckers (118-248 µm), a tegument covered with tiny spines, a larger cone genital (193-361 × 296-637) and a larger copulatory bursa (247-531 × 468-784). Our phylogenetic analyses revealed that P. macrobursa is not closely related to other members of the genus Parastrigea and is nested within Strigea, suggesting that P. macrobursa should be transferred to Strigea to form Strigea macrobursa n. comb., expanding its distribution range from Mexico to Argentina. Finally, the analyses also revealed that the taxonomy and systematics of Strigea should be re-evaluated, combining morphological and molecular characteristics.


Asunto(s)
Rapaces , Trematodos , Animales , Filogenia , Teorema de Bayes , Aves , ADN Ribosómico/genética , México , ADN de Helmintos/genética
14.
J Helminthol ; 97: e31, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36960830

RESUMEN

Adult specimens of Andracantha gravida (Alegret, 1941) were recorded from the intestines of the double-crested cormorant Nannopterum auritus (Lesson) (type host) and brown pelican Pelecanus occidentalis L. in two localities from Mexico: Celestún, Yucatan (south-eastern) and Punta Piedra, Tamaulipas (north-eastern). The specimens of A. gravida are morphologically characterized by having a pipe-shaped body without swellings, the absence of small trunk spines between the two fields of spines on the foretrunk and a cylindrical proboscis with 14-16 rows of 10-12 hooks per row. Newly generated partial sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were generated from adult isolates of A. gravida from Mexico and compared with one sequence of A. gravida and with sequences of other polymorphid acanthocephalans available in GenBank. Phylogenetic analyses based on maximum likelihood and Bayesian inference methods of the cox1 dataset placed all the species of Andracantha in a single clade, with weak support. The analyses of the cox1 dataset placed Andracantha sigma Presswell, García-Varela & Smales, , as sister to the clade formed by A. gravida, Andracantha phalacrocoracis (Yamaguti, 1939), Andracantha leucocarboi Presswell, García-Varela & Smales, and an unidentified species of Andracantha from Japan. The newly generated cox1 sequences of A. gravida from piscivorous birds of Mexico formed a strongly supported clade with the published sequence of A. gravida from the double-crested cormorant from the south-eastern coast of Mexico. The intraspecific genetic divergence among isolates identified as A. gravida ranged from 0.0% to 2.2%. A cox1 haplotype network inferred with 14 sequences revealed the presence of nine haplotypes, two of which were shared between the populations of piscivorous birds from the north-eastern and south-eastern coasts of Mexico and seven of which were unique. The fixation index between the populations from north-eastern and south-eastern Mexico was low (0.06949), which suggests genetic flow. This can be explained by the migration patterns of the brown pelican and the double-crested cormorant along the coasts of the Gulf of Mexico.


Asunto(s)
Acantocéfalos , Animales , Filogenia , Golfo de México , Teorema de Bayes , Aves , México
15.
J Helminthol ; 97: e98, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38095098

RESUMEN

Scaphanocephalus is a small trematode genus belonging to the family Opistorchiidae. The genus currently contains only three species associated with marine fish as intermediate hosts and fish-eating birds as definitive hosts. Here, specimens of Scaphanocephalus were collected from the Osprey, Pandion haliaetus, and the White mullet, Mugil curema in the Yucatán Peninsula, Mexico. We report for the first-time DNA sequences of adult specimens of Scaphanocephalus, particularly S. expansus, as well as a sequence of a different species sampled as metacercaria. Morphological comparisons of Scaphanocephalus expansus confirmed the identity of the adult specimens, with minor morphological variations; Scanning electron photomicrographs were included, and the species was re-described. Phylogenetic analysis based on 28S rDNA sequences showed that Scaphanocephalus is monophyletic within Opisthorchiidae and consists of three independent lineages. Sequences of adults are identical to those of S. expansus. Instead, the sequence of the metacercaria sampled from the mesentery of Mugil curema nested with specimens reported as Scaphanocephalus sp. from a labrid fish in the Mediterranean Sea, herein named it as Scaphanocephalus sp. 2.


Asunto(s)
Falconiformes , Enfermedades de los Peces , Heterophyidae , Smegmamorpha , Trematodos , Infecciones por Trematodos , Animales , México , Filogenia , ADN de Helmintos/genética , Heterophyidae/genética , Peces , Metacercarias , Infecciones por Trematodos/veterinaria
16.
Med Oral Patol Oral Cir Bucal ; 28(1): e32-e40, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36243992

RESUMEN

BACKGROUND: The aim of this research is to evaluate the periodontal health of patients with Parkinson Disease (PD) in a Spanish cohort. MATERIAL AND METHODS: A cross-sectional study was performed on 104 patients with PD (mean age: 66.19+9.3 years) and 106 controls (mean age: 59.26+14.11 years). A pre-designed clinical protocol was implemented, which included a standardized epidemiological index for periodontal disease (CPITN), clinical attachment loss (CAL), tooth-loss, full mouth plaque index (FMPI), and oral hygienic habits. Univariate descriptions and comparative analysis were performed. RESULTS: The majority of PD patients presented good oral hygienic habits. There were no significant differences in relation to CPITN, periodontitis, gingival recessions and tooth loss. However, moderate/severe CAL (p=0.027) and FMPI (p=0.003) was higher in the PD group. CONCLUSIONS: There were no differences on periodontitis and tooth loss between both groups. The higher number of advanced CAL and presence of biofilm in the PD group could be related to the difficulties to perform an effective tooth brushing due to this neurological disorder.


Asunto(s)
Enfermedad de Parkinson , Periodontitis , Pérdida de Diente , Humanos , Persona de Mediana Edad , Anciano , Estudios Transversales , Enfermedad de Parkinson/complicaciones , España/epidemiología , Periodontitis/complicaciones , Periodontitis/epidemiología
17.
Phys Chem Chem Phys ; 24(7): 4515-4525, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35119058

RESUMEN

We calculate the relative energy between the cumulene and polyyne structures of a set of C4k+2 (k = 4-7) rings (C18, C22, C26, and C30 prompted by the recent synthesis of the cyclo[18]carbon (or simply C18) compounds. Reference results were obtained by a costly Quantum Monte-Carlo (QMC) approach, providing thus very accurate values allowing to systematically compare the performance of a variety of wavefunction methods [(i.e., MP2, SCS-MP2, SOS-MP2, DLPNO-CCSD, and DLPNO-CCSD(T)] as well as DFT approaches, applying for the latter a diversity of density functionals covering global and range-separated hybrid and double-hybrid models. The influence of the use of a range-separation scheme for density functionals, for both hybrid and double-hybrid expressions, is discussed according to its key role. Overall, range-separated double-hybrid functionals (e.g., RSX-QIDH) behave very accurately and provide competitive results compared with DLPNO-CCSD(T), at a more reasonable computational cost.

18.
J Chem Phys ; 156(3): 034105, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35065561

RESUMEN

The energy difference (ΔEST) between the lowest singlet (S1) state and the triplet (T1) excited state of a set of azaphenalene compounds, which is theoretically and experimentally known to violate Hund's rule, giving rise to the inversion of the order of those states, is calculated here with a family of double-hybrid density functionals. That excited-state inversion is known to be very challenging to reproduce for time-dependent density functional theory employing common functionals, e.g., hybrid or range-separated expressions, but not for wavefunction methods due to the inclusion of higher-than-single excitations. Therefore, we explore here if the last developed family of density functional expressions (i.e., double-hybrid models) is able to provide not only the right excited-state energy order but also accurate ΔEST values, thanks to the approximate inclusion of double excitations within these models. We herein employ standard double-hybrid (B2-PLYP, PBE-QIDH, and PBE0-2), range-separated (ωB2-PLYP and RSX-QIDH), spin-scaled (SCS/SOS-B2PLYP21, SCS-PBE-QIDH, and SOS-PBE-QIDH), and range-separated spin-scaled (SCS/SOS-ωB2-PLYP, SCS-RSX-QIDH, and SOS-RSX-QIDH) expressions to systematically assess the influence of the ingredients entering into the formulation while concomitantly providing insights for their accuracy.

19.
J Investig Allergol Clin Immunol ; 32(4): 270-281, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-33884956

RESUMEN

BACKGROUND AND OBJECTIVE: Nut allergy is a growing problem, yet little is known about its onset in children. Objective: To characterize the onset of nut allergy in children in southern Europe. METHODS: The study population comprised consecutive patients up to 14 years of age who visited allergy departments with an initial allergic reaction to peanut, tree nut, or seed. The allergy work-up included a clinical history, food challenge, skin prick testing, determination of whole-extract sIgE, and ImmunoCAP ISAC-112 assay. RESULTS: Of the 271 children included, 260 were first diagnosed with nut allergy at a mean age of 6.5 years and at a mean (SD) of 11.8 (21.2) months after the index reaction. The most common culprit nuts at onset were walnut (36.5%), peanut (28.5%), cashew (10.4%), hazelnut (8.5%), pistachio (5.4%), and almond (5%). Onset of peanut allergy was more frequent in children ≤6 years and walnut in those aged >6 years (P=.032). In 65% of cases, the allergic reaction occurred the first time the patient consumed the nut, and 35% of reactions were anaphylactic. Overall, polysensitization to nuts was detected by skin prick testing in 64.9% of patients, although this rate was lower among walnut-allergic children (54.7%) and peanut-allergic children (54.1%) (P<.0001). Sensitization to 2S albumins was predominant (75%), especially Jug r 1 (52.8%), whereas sensitization to lipid transfer proteins was less relevant (37%). CONCLUSION: In the population we assessed, the onset of nut allergy occurred around 6 years of age, slightly later than that reported in English-speaking countries. Walnut was the main trigger, followed by peanut. 2S albumin storage proteins, especially Jug r 1, were the most relevant allergens. This study will help guide management and may contribute to preventive strategies in pediatric nut allergy.


Asunto(s)
Juglans , Hipersensibilidad a la Nuez , Hipersensibilidad al Cacahuete , Alérgenos , Arachis , Niño , Humanos , Inmunoglobulina E , Hipersensibilidad a la Nuez/diagnóstico , Hipersensibilidad a la Nuez/epidemiología , Nueces , Hipersensibilidad al Cacahuete/diagnóstico , Pruebas Cutáneas
20.
Eur J Public Health ; 32(6): 894-899, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36083204

RESUMEN

BACKGROUND: The lack of systematic factors affecting physical inactivity (PIA) challenges policymakers to implement evidence-based solutions at a population level. The study utilizes the Eurobarometer to analyse PIA-modifiable variables. METHODS: Special Eurobarometer 412 physical activity (PA) data were analysed (n = 18 336), including 40 variables along with the International PA Questionnaire. PIA was used as the dependent variable. Variables considered were alternatives to car, places, reasons and barriers to engaging in PA, memberships to clubs and categorical responses about the agreement extent with the area, provision of activities and local governance statements. Logistic regression was used to identify variables contributing to PIA. Beta values (ß), standard errors, 95% confidence intervals, the exponentiation for odds ratio and Cox & Snell and Nagelkerke R2 were indicated. RESULTS: The resulting model correctly identified 10.7% inactives and 96.9% of actives (R2 of Nagelkerke: 0.153). Variables contributing to the detection of PIA were (P ≤ 0.01): having a disability or an illness, not having friends to do sport with, lacking motivation or interest in and being afraid of injury risk. Additionally, totally agreeing, tend to agree and tend to disagree regarding the extent of local providers offering enough opportunities to be more active also contributed to the model. CONCLUSIONS: The model reported a limited ability to detect modifiable factors affecting PIA, identifying a small percentage of inactive individuals correctly. New questions focused on understanding inactive behaviour are needed to support the European PA public health agenda.


Asunto(s)
Personas con Discapacidad , Deportes , Humanos , Conducta Sedentaria , Ejercicio Físico , Motivación
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