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1.
Phys Rev E ; 104(3-2): 035303, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34654121

RESUMEN

Time periodic patterns in a semiconductor superlattice, relevant to microwave generation, are obtained upon numerical integration of a known set of drift-diffusion equations. The associated spatiotemporal transport mechanisms are uncovered by applying (to the computed data) two recent data processing tools, known as the higher order dynamic mode decomposition and the spatiotemporal Koopman decomposition. Outcomes include a clear identification of the asymptotic self-sustained oscillations of the current density (isolated from the transient dynamics) and an accurate description of the electric field traveling pulse in terms of its dispersion diagram. In addition, a preliminary version of a data-driven reduced order model is constructed, which allows for extremely fast online simulations of the system response over a range of different configurations.

2.
J Investig Allergol Clin Immunol ; 31(1): 58-64, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-31599726

RESUMEN

BACKGROUND AND OBJECTIVE: The Global Initiative for Asthma (GINA) recommends the concurrent use of self-report and pharmacy refill data to assess treatment adherence. However, clinical evidence to support this combined approach is limited. Objective: To determine nonadherence to inhaler medication based on a validated questionnaire (Test of Adherence to Inhalers; TAI) and prescription refill data in a community sample of patients with chronic obstructive pulmonary disease (COPD) or asthma. Secondarily, we sought to determine the degree of concordance between these two measures. METHODS: Cross-sectional, observational multicenter study in patients with asthma or COPD. Sociodemographic and clinical data were obtained from clinical records. Refill data were retrieved from electronic pharmacy databases. Participants completed the 12-item TAI during a single visit as part of routine care. Nonadherence was defined as TAI <50 or <80% pharmacy refill rate (PRR) in the previous 6 months. RESULTS: A total of 816 patients (mean age, 60) were included. Nonadherence rates were 58.1% (TAI) and 28.6% (PRR) compared with 64.6% for the combined data (P<.0001). Concordance between the 2 measures was weak (к=0.205). CONCLUSIONS: These findings confirm the GINA recommendations, indicating that concomitant use of the TAI and pharmacy refill data identifies a higher percentage of nonadherent asthma or COPD patients than either instrument alone.


Asunto(s)
Asma/tratamiento farmacológico , Cumplimiento de la Medicación/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Asma/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nebulizadores y Vaporizadores , Prescripciones , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Autoinforme , España/epidemiología , Encuestas y Cuestionarios
3.
J Chem Theory Comput ; 15(7): 4252-4263, 2019 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-31142108

RESUMEN

A computational protocol has been applied to the alanine dipeptide model in order to study the side-chain conformation, the calculated spin-spin coupling constants involved in the side-chain χ1 angle, and theoretical extended Karplus equations developed for amino acids. Two structures within the backbone secondary conformation are used to predict coupling constants which in addition are employed to analyze the effect of those structures on the resulting Karplus extended equations. The number of Fourier coefficients to be included within the Karplus equations is critically analyzed. Wave function and density functional methods as well as different basis sets are compared to find appropriate Karplus coefficients in the most efficient way. The influence of exchange and correlation functionals and the solvent effect on the calculated couplings are considered.


Asunto(s)
Aminoácidos/química , Simulación por Computador , Dipéptidos/química , Alanina/química , Teoría Funcional de la Densidad , Análisis de Fourier , Modelos Moleculares
4.
Phys Rev Lett ; 120(9): 099901, 2018 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-29547308

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.118.024501.

5.
J Mol Model ; 23(4): 134, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28341995

RESUMEN

Spin-spin coupling constants in water monomer and dimer have been calculated using several wave function and density functional-based methods. CCSD, MCSCF, and SOPPA wave functions methods yield similar results, specially when an additive approach is used with the MCSCF. Several functionals have been used to analyze their performance with the Jacob's ladder and a set of functionals with different HF exchange were tested. Functionals with large HF exchange appropriately predict 1 J O H , 2 J H H and 2h J O O couplings, while 1h J O H is better calculated with functionals that include a reduced fraction of HF exchange. Accurate functionals for 1 J O H and 2 J H H have been tested in a tetramer water model. The hydrogen bond effects on these intramolecular couplings are additive when they are calculated by SOPPA(CCSD) wave function and DFT methods. Graphical Abstract Evaluation of the additive effect of the hydrogen bond on spin-spin coupling constants of water using WF and DFT methods.

6.
Phys Rev Lett ; 118(2): 024501, 2017 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-28128625

RESUMEN

We examine both theoretically and experimentally the breakup of a pendant drop loaded with an insoluble surfactant. The experiments show that a significant amount of surfactant is trapped in the resulting satellite droplet. This result contradicts previous theoretical predictions, where the effects of surface tension variation were limited to solutocapillarity and Marangoni stresses. We solve numerically the hydrodynamic equations, including not only those effects but also those of surface shear and dilatational viscosities. We show that surface viscosities play a critical role to explain the accumulation of surfactant in the satellite droplet.

7.
Clin Transl Oncol ; 19(5): 616-624, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27853985

RESUMEN

PURPOSE: To converge on an expert opinion to define aggressive disease in patients with HER2-negative mBC using a modified Delphi methodology. METHODS: A panel of 21 breast cancer experts from the Spanish Society of Medical Oncology agreed upon a survey which comprised 47 questions that were grouped into three sections: relevance for defining aggressive disease, aggressive disease criteria and therapeutic goals. Answers were rated using a 9-point Likert scale of relevance or agreement. RESULTS: Among the 88 oncologists that were invited to participate, 81 answered the first round (92%), 70 answered the second round (80%), and 67 answered the third round (76%) of the survey. There was strong agreement regarding the fact that identifying patients with aggressive disease needs to be adequately addressed to help practitioners to decide the best treatment options for patients with HER2-negative mBC. The factors that were considered to be strongly relevant to classifying patients with aggressive HER2-negative mBC were a high tumor burden, a disease-free interval of less than 12-24 months after surgery, the presence of progressive disease during adjuvant or neoadjuvant chemotherapy and having a triple-negative phenotype. The main therapeutic goals were controlling symptoms, improving quality of life and increasing the time to progression and overall survival. CONCLUSIONS: High tumor burden, time to recurrence after prior therapy and having a triple-negative phenotype were the prognostic factors for which the greatest consensus was found for identifying patients with aggressive HER2-negative mBC. Identifying patients with aggressive disease leads to different therapeutic approaches.


Asunto(s)
Neoplasias de la Mama/clasificación , Neoplasias de la Mama/patología , Oncología Médica/normas , Consenso , Técnica Delphi , Femenino , Humanos , Receptor ErbB-2 , Sociedades Médicas
8.
Front Microbiol ; 7: 1880, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27933043

RESUMEN

Flavobacterium psychrophilum is the most important bacterial pathogen for freshwater farmed salmonids in Chile. The aims of this study were to determine the susceptibility to antimicrobials used in fish farming of Chilean isolates and to calculate their epidemiological cut-off (COWT) values. A number of 125 Chilean isolates of F. psychrophilum were isolated from reared salmonids presenting clinical symptoms indicative of flavobacteriosis and their identities were confirmed by 16S rRNA polymerase chain reaction. Susceptibility to antibacterials was tested on diluted Mueller-Hinton by using an agar dilution MIC method and a disk diffusion method. The COWT values calculated by Normalized Resistance Interpretation (NRI) analysis allow isolates to be categorized either as wild-type fully susceptible (WT) or as manifesting reduced susceptibility (NWT). When MIC data was used, NRI analysis calculated a COWT of ≤0.125, ≤2, and ≤0.5 µg mL-1 for amoxicillin, florfenicol, and oxytetracycline, respectively. For the quinolones, the COWT were ≤1, ≤0.5, and ≤0.125 µg mL-1 for oxolinic acid, flumequine, and enrofloxacin, respectively. The disk diffusion data sets obtained in this work were extremely diverse and were spread over a wide range. For the quinolones there was a close agreement between the frequencies of NWT isolates calculated using MIC and disk data. For oxolinic acid, flumequine, and enrofloxacin the frequencies were 45, 39, and 38% using MIC data, and 42, 41, and 44%, when disk data were used. There was less agreement with the other antimicrobials, because NWT frequencies obtained using MIC and disk data, respectively, were 24 and 10% for amoxicillin, 8 and 2% for florfenicol, and 70 and 64% for oxytetracycline. Considering that the MIC data was more precise than the disk diffusion data, MIC determination would be the preferred method for susceptibility testing for this species and the NWT frequencies derived from the MIC data sets should be considered as the more authoritative. Despite the high frequency of isolates showing full susceptibility to florfenicol, the significant frequencies of isolates exhibiting reduced susceptibility to oxytetracycline and quinolones may result in treatment failures when these agents are used.

9.
Phys Med ; 32(12): 1551-1558, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27890566

RESUMEN

BACKGROUND AND PURPOSE: The study objective was to report our four-and-a half years experience (March 1 2011-August 15 2015) of a program to manage interruptions in fractionated radiotherapy treatments. METHODS: A program was developed, based on a specific database, to manage treatment interruptions. Benefits of the program were analyzed in reference to previously published data. Analysis was also performed of two measures to reduce OTT prolongation and improve treatment outcomes: working on public holidays and conducting treatment unit maintenance on Saturdays. RESULTS: The study included 2352 patients. Patients with head and neck cancer obtained the greatest benefit from the program, with a mean increase in TCP of 3.5% and a benefit of at least 4% in 45.6% of them. In prostate cancer patients, the likelihood of biochemical failure was reduced by a mean of 2.0% and was reduced by at least 4% in 19.7% of them. Application of the two proposed measures would have improved the TCP by a mean of 5.4% in head and neck cancer patients. The impact of the compensations program and proposed measures is lesser in the remaining cancer types studied. CONCLUSIONS: Implementation of a compensation program has a significant impact on patients with head and neck or prostate cancer but OTT prolongation remains excessive in many treatments. The introduction of fractions on public holidays would assist in the meeting of recommendations for these patients.


Asunto(s)
Fraccionamiento de la Dosis de Radiación , Radioterapia/métodos , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Neoplasias de la Próstata/radioterapia , Factores de Tiempo
10.
J Chem Phys ; 145(8): 084301, 2016 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-27586916

RESUMEN

The effect of a fraction of Hartree-Fock exchange on the calculated spin-spin coupling constants involving fluorine through a hydrogen bond is analyzed in detail. Coupling constants calculated using wavefunction methods are revisited in order to get high-level calculations using the same basis set. Accurate MCSCF results are obtained using an additive approach. These constants and their contributions are used as a reference for density functional calculations. Within the density functional theory, the Hartree-Fock exchange functional is split in short- and long-range using a modified version of the Coulomb-attenuating method with the SLYP functional as well as with the original B3LYP. Results support the difficulties for calculating hydrogen bond coupling constants using density functional methods when fluorine nuclei are involved. Coupling constants are very sensitive to the Hartree-Fock exchange and it seems that, contrary to other properties, it is important to include this exchange for short-range interactions. Best functionals are tested in two different groups of complexes: those related with anionic clusters of type [F(HF)n](-) and those formed by difluoroacetylene and either one or two hydrogen fluoride molecules.

11.
Eur Radiol ; 26(12): 4268-4276, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27384609

RESUMEN

OBJECTIVES: To propose national diagnostic reference levels (DRLs) for interventional radiology and to evaluate the impact of the procedural complexity on patient doses. METHODS: Eight interventional radiology units from Spanish hospitals were involved in this project. The participants agreed to undergo common quality control procedures for X-ray systems. Kerma area product (KAP) was collected from a sample of 1,649 procedures. A consensus document established the criteria to evaluate the complexity of seven types of procedures. DRLs were set as the 3rd quartile of KAP values. RESULTS: The KAP (3rd quartile) in Gy cm2 for the procedures included in the survey were: lower extremity arteriography (n = 784) 78; renal arteriography (n = 37) 107; transjugular hepatic biopsies (THB) (n = 30) 45; biliary drainage (BD) (n = 314) 30; uterine fibroid embolization (UFE) (n = 56) 214; colon endoprostheses (CE) (n = 31) 169; hepatic chemoembolization (HC) (n = 269) 303; femoropopliteal revascularization (FR) (n = 62) 119; and iliac stent (n = 66) 170. The complexity involved the increases in the following KAP factors from simple to complex procedures: THB x4; BD x13; UFE x3; CE x3; HC x5; FR x5 and IS x4. CONCLUSIONS: The evaluation of the procedure complexity in patient doses will allow the proper use of DRLs for the optimization of interventional radiology. KEY POINTS: • National DRLs for interventional procedures have been proposed given level of complexity • For clinical audits, the level of complexity should be taken into account. • An evaluation of the complexity levels of the procedure should be made.


Asunto(s)
Angiografía/métodos , Angiografía/normas , Control de Calidad , Radiología Intervencionista/métodos , Radiología Intervencionista/normas , Femenino , Humanos , Dosis de Radiación , Valores de Referencia , España , Encuestas y Cuestionarios
13.
Allergy ; 70(10): 1332-5, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26119056

RESUMEN

Thaumetopoea pityocampa causes allergies and skin and ocular lesions. No commercial tools are currently available for the clinical diagnosis of this allergy. We aimed to develop an in vitro method for the diagnosis of this allergy to avoid patients undergoing in vivo tests with insect extracts. Recombinant Tha p 2 was produced and used in an ELISA validated with 15 allergic patients. Subsequently, 42 subjects recruited from a random sampling cross-sectional study were analysed. The ELISA sensitivity and specificity were 93.3% and 100%, respectively, for the allergic patients and 71.4% and 95.3%, respectively, for the epidemiological study. The positive ELISA results correlated with the skin prick test areas with the whole body and the setae extracts. Professional exposure and short latency of symptoms onset were risk factors for a positive result in the ELISA. In conclusion, our ELISA is very useful for T. pityocampa allergy diagnosis and for epidemiologic testing.


Asunto(s)
Alérgenos/inmunología , Hipersensibilidad/diagnóstico , Hipersensibilidad/inmunología , Proteínas de Insectos/inmunología , Mariposas Nocturnas/inmunología , Proteínas Recombinantes/inmunología , Animales , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Humanos
14.
Allergol Immunopathol (Madr) ; 43(1): 73-80, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24961955

RESUMEN

BACKGROUND: Eosinophilic oesophagitis (EoE) is a disorder characterised by oesophageal dysfunction and, histologically, by eosinophilic inflammation. Although treatment, which includes dilatations, oral corticosteroids and restrictive diets, is often effective, choosing the foods to be eliminated from the diet is difficult. OBJECTIVE: Component resolved diagnostic by microarray allergen assay may be useful in detecting allergens that might be involved in the inflammatory process. METHODS: We studied 67 patients with EoE, diagnosed clinically and histologically by endoscopic biopsy. CRD analysis with microarray technology was carried out in the 67 EoE patients, 50 patients with pollen allergy without digestive symptoms, and 50 healthy controls. RESULTS: Allergies were not detected by microarray in only seven of the 67 patients with EoE. Controls with pollen allergy showed sensitisation to different groups of pollen proteins without significant differences. In EoE patients with response to some allergens, the predominant allergens were grasses group 1 and, in particular, nCyn d 1 (Cynodon dactylon) or Bermuda grass pollen in 59.5%, followed by lipid transfer proteins (LTP) of peach (19.40%), hazelnut (17.91%) and Artemisia (19.40%). CONCLUSIONS: In patients with EoE, sensitisation to plant foods and pollen is important. The proteins most frequently involved are nCyn d 1 and lipid transfer proteins, hazelnuts and walnuts. After one year of an array-guided exclusion diet and pollen-specific immunotherapy in the case of high levels of response, patients with EoE showed preliminary significant improvements.


Asunto(s)
Desensibilización Inmunológica , Esofagitis Eosinofílica/diagnóstico , Análisis por Micromatrices/métodos , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/terapia , Adolescente , Adulto , Antígenos de Plantas/inmunología , Artemisia/inmunología , Proteínas Portadoras/inmunología , Corylus/inmunología , Cynodon/inmunología , Esofagitis Eosinofílica/dietoterapia , Conducta Alimentaria , Femenino , Humanos , Masculino , Proteínas de Plantas/inmunología , Polen/inmunología , Prunus/inmunología , Rinitis Alérgica Estacional/inmunología , Adulto Joven
15.
J Phys Chem A ; 118(51): 12120-9, 2014 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-25429771

RESUMEN

Classical trajectories have been integrated to study the O + ClO reaction, both reactive and vibrational energy transfer processes, for the range of temperatures 100 ≤ T/K ≤ 500 using momentum Gaussian binning. The employed potential energy surface is the recently proposed single-sheeted double many-body expansion potential energy surface for the (2)A" ground-state of ClO2 based on multireference ab initio data. A capture-type regime with a room-temperature rate constant of (17.8 ± 0.5) × 10(-12) cm(3) s(-1) and temperature dependence of k(T/K)/cm(3) s(-1) = 22.4 × 10(-12) × T(-0.81) exp(-39.2/T) has been found. Although the value reported here is half of the experimental and recommended one, tentative explanations are given. Other dynamical attributes are also examined for the title reaction, with state-to-all and state-to-state vibrational relaxation and excitation rate constants reported for temperatures of relevance in stratospheric chemistry.

16.
J Phys Chem A ; 118(26): 4851-62, 2014 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-24915054

RESUMEN

A global single-sheeted double many-body expansion potential energy surface is reported for the ground electronic state of ClO2. The potential energy surface is obtained by fitting 3200 energy points that map all atom-diatom dissociation channels as well as all relevant stationary points, including the well-known OClO and ClOO structures. The ab initio calculations are obtained at the multireference configuration interaction level of theory, employing the cc-pVXZ (X = D, T) Dunning basis sets, and then extrapolated to the complete basis set limit with the generalized uniform singlet- and triplet-pair protocol. The topographical features of the novel global potential energy surface are examined in detail.

17.
Phys Med ; 30(7): 827-32, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24735905

RESUMEN

The relation between the data recorded with any device for the daily checking of the behavior of a clinical linac and the reference magnitudes to be monitored may be unknown. An experimental method relating the energy stability of the electron beam measured with StarTrack(®) to the R50 beam quality index is proposed. The bending magnet current is varied producing a change in the exit energy window and, therefore, a modification of the R50 value. For different values of this current, the output data of StarTrack(®) and the R50, obtained from depth doses measured in a water phantom are determined. A linear fit between both sets of data allows the identification of the StarTrack(®) output that provides the best way to obtain the quality index R50, for each beam nominal energy. Using these fits, an historical datum series is used to analyze the method proposed in the daily quality control. The ouput data of the StarTrack(®) and the R50 values show a good linear correlation. It is possible to establish a methodology that allows the monitoring of R50 by direct use of the daily quality control data measured with StarTrack(®). A method to monitor R50 in the daily quality control using the StarTrack(®) device has been developed. The method may be applied to similar devices in which the statistical control variable does not show a linear behavior with R50.


Asunto(s)
Aceleradores de Partículas/normas , Electrones , Imanes , Control de Calidad , Radiometría , Valores de Referencia
18.
J Chem Theory Comput ; 10(11): 4938-49, 2014 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-26584378

RESUMEN

Different types of spin-spin coupling constants (SSCCs) for several representative small molecules are evaluated and analyzed using a combination of 10 exchange functionals with 12 correlation functionals. For comparison, calculations performed using MCSCF, SOPPA, other common DFT methods, and also experimental data are considered. A detailed study of the percentage of Hartree-Fock exchange energy in SSCCs and in its four contributions is carried out. From the above analysis, a combined functional formed with local Slater (34%), Hartree-Fock exchange (66%), and P86 correlation functional (S66P86) is proposed in this paper. The accuracy of the values obtained with this hybrid functional (mean absolute deviation of 4.5 Hz) is similar to that of the SOPPA method (mean absolute deviation of 4.6 Hz).

19.
Magn Reson Chem ; 51(12): 775-87, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24123317

RESUMEN

Optimized shifting and/or scaling factors for calculating one-bond carbon-hydrogen spin-spin coupling constants have been determined for 35 combinations of representative functionals (PBE, B3LYP, B3P86, B97-2 and M06-L) and basis sets (TZVP, HIII-su3, EPR-III, aug-cc-pVTZ-J, ccJ-pVDZ, ccJ-pVTZ, ccJ-pVQZ, pcJ-2 and pcJ-3) using 68 organic molecular systems with 88 (1)JCH couplings including different types of hybridized carbon atoms. Density functional theory assessment for the determination of (1)JCH coupling constants is examined, comparing the computed and experimental values. The use of shifting constants for obtaining the calculated coupling improves substantially the results, and most models become qualitatively similar. Thus, for the whole set of couplings and for all approaches excluding those using the M06 functional, the root-mean-square deviations lie between 4.7 and 16.4 Hz and are reduced to 4-6.5 Hz when shifting constants are considered. Alternatively, when a specific rovibrational contribution of 5 Hz is subtracted from the experimental values, good results are obtained with PBE, B3P86 and B97-2 functionals in combination with HIII-su3, aug-cc-pVTZ-J and pcJ-2 basis sets.


Asunto(s)
Teoría Cuántica , Espectroscopía de Resonancia Magnética/normas , Estándares de Referencia
20.
Forensic Sci Int ; 231(1-3): e11-8, 2013 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-23845917

RESUMEN

We present a forensic case associated with skeletonized human remains found inside a cistern in a coastal town located in the eastern Iberian Peninsula (Valencian Regional Government, Spain). In order to analyse the particular environmental conditions that occurred during oviposition and development of the collected insects, estimated temperatures at the crime scene were calculated by a predictive mathematical model. This model analyses the correlation between the variability of the internal temperature depending on the variability of the external ones. The amplitude of the temperature oscillations inside the tank and the containment of the enclosure is reduced by the presence of water. Such variation occurred within about 2h due to the time required for heat exchange. The differential equations employed to model differences between outdoor and indoor temperatures were an essential tool which let us estimate the post-mortem interval (PMI) that was carried out by the study of the insect succession and the development time of the collected Diptera specimens under the adjusted temperatures. The presence of live larvae and pupae of Sarcophagidae and empty pupae of Calliphoridae, Sarcophagidae, Fanniidae, Muscidae, Phoridae and Piophilidae and the decomposition stage suggested the possibility that the remains were in the tank at least a year. We highlight the absence of Calliphora and Lucilia spp., and the first occurrence of the phorid Conicera similis in a human cadaver among the entomological evidence.


Asunto(s)
Dípteros/crecimiento & desarrollo , Conducta Alimentaria , Modelos Teóricos , Cambios Post Mortem , Animales , Espacios Confinados , Oscuridad , Dípteros/fisiología , Entomología , Patologia Forense , Humanos , Larva , Oviposición , Pupa , España , Temperatura
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