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1.
Eur J Appl Physiol ; 122(4): 1007-1017, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35142944

RESUMEN

PURPOSE: In young adults, the hormonal responses to resistance exercise are amplified by normobaric hypoxia. Hormone concentrations and metabolism are typically dysregulated with age, yet the impact of hypoxia on these responses to resistance exercise are uncharacterised. Therefore, this study aimed to characterise the acute and chronic hormonal and metabolic responses of older adults to resistance training in normobaric hypoxia. METHODS: Adults aged 60-75 years completed 8 weeks of resistance training in either normoxia (20.9% O2; n = 10) or normobaric hypoxia (14.4% O2, n = 10) twice weekly at 70% of their predicted 1-repetition maximum. Growth hormone, glucose, lactate, insulin, homeostatic model assessment of insulin resistance (HOMA-IR), cortisol, total testosterone, adrenaline, noradrenaline and dopamine were quantified at pre- and post-training, and in the 60 min following the first training session (untrained state) and the last training session (trained state). RESULTS: Eight weeks of training in hypoxia did not affect the resting levels of the hormones or physiological factors measured. However, hypoxia significantly blunted the acute growth hormone response in the 15 min following the last training session at week eight (43.87% lower in the hypoxic group; p = 0.017). This novel and unexpected finding requires further investigation. All other hormones were unaffected acutely by hypoxia in the 60 min following the first and the last training session. CONCLUSION: Chronic resistance training in normobaric hypoxia supresses the growth hormone response to exercise in older adults. All other hormones and metabolic markers were unaffected both acutely and chronically by hypoxia.


Asunto(s)
Hormona de Crecimiento Humana , Entrenamiento de Fuerza , Anciano , Ejercicio Físico/fisiología , Humanos , Hipoxia , Insulina , Persona de Mediana Edad , Adulto Joven
2.
Phys Chem Chem Phys ; 23(3): 2141-2153, 2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33437976

RESUMEN

We report a comprehensive study on the electronic excited states of tetrafluoro-1,4-benzoquinone, through high-resolution vacuum ultraviolet photoabsorption spectroscopy and time-dependent density functional theory calculations performed within the nuclear ensemble approach. Absolute cross section values were experimentally determined in the 3.8-10.8 eV energy range. The present experimental results represent the highest resolution data yet reported for this molecule and reveal previously unresolved spectral structures. The interpretation of the results was made in close comparison with the available data for para-benzoquinone [Jones et al., J. Chem. Phys., 2017, 146, 184303]. While the dominant absorption features for both molecules arise from analogous π* ← π transitions, some remarkable differences have been identified. The perfluoro effect manifests in different ways: shifts in band positions and cross sections, appearance of features associated with excitations to σCF* orbitals, and spectrum broadening by quenching of either vibrational or Rydberg progressions. The level of agreement between experiment and theory is very satisfactory, yet that required the inclusion of nuclear quantum effects in the calculations. We have also discussed the role of temperature on the absorption spectrum, as well as the involvement of core-excited resonances in promoting dissociative electron attachment reactions in the 3-5 eV range.

3.
BMC Neurol ; 19(1): 148, 2019 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-31269910

RESUMEN

BACKGROUND: Almost 40% of stroke patients have a poor outcome at 3 months after the index event. Predictors for stroke outcome in the early acute phase may help to tailor stroke treatment. Infection and inflammation are considered to influence stroke outcome. METHODS: In a prospective multicenter study in Germany and Spain, including 486 patients with acute ischemic stroke, we used multivariable regression analysis to investigate the association of poor outcome with monocytic HLA-DR (mHLA-DR) expression, interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-alpha) and lipopolysaccharide-binding protein (LBP) as markers for immunodepression, inflammation and infection. Outcome was assessed at 3 months after stroke via a structured telephone interview using the modified Rankin Scale (mRS). Poor outcome was defined as a mRS score of 3 or higher which included death. Furthermore, a time-to-event analysis for death within 3 months was performed. RESULTS: Three-month outcome data was available for 391 patients. Female sex, older age, diabetes mellitus, atrial fibrillation, stroke-associated pneumonia (SAP) and higher National Institute of Health Stroke Scale (NIHSS) score as well as lower mHLA-DR levels, higher IL-6 and LBP-levels at day 1 were associated with poor outcome at 3 months in bivariate analysis. Furthermore, multivariable analysis revealed that lower mHLA-DR expression was associated with poor outcome. Female sex, older age, atrial fibrillation, SAP, higher NIHSS score, lower mHLA-DR expression and higher IL-6 levels were associated with shorter survival time in bivariate analysis. In multivariable analysis, SAP and higher IL-6 levels on day 1 were associated with shorter survival time. CONCLUSIONS: SAP, lower mHLA-DR-expression and higher IL-6 levels on day one are associated with poor outcome and shorter survival time at 3 months after stroke onset. TRIAL REGISTRATION: www.clinicaltrials.gov, NCT01079728 , March 3, 2010.


Asunto(s)
Isquemia Encefálica/inmunología , Antígenos HLA-DR/sangre , Interleucina-6/sangre , Neumonía/etiología , Accidente Cerebrovascular/inmunología , Proteínas de Fase Aguda , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/complicaciones , Biomarcadores/sangre , Isquemia Encefálica/sangre , Isquemia Encefálica/complicaciones , Isquemia Encefálica/mortalidad , Proteínas Portadoras/sangre , Diabetes Mellitus , Femenino , Alemania , Humanos , Tolerancia Inmunológica , Inflamación/complicaciones , Interleucina-10/sangre , Masculino , Glicoproteínas de Membrana/sangre , Persona de Mediana Edad , Neumonía/mortalidad , Estudios Prospectivos , España , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/mortalidad , Factores de Tiempo , Factor de Necrosis Tumoral alfa/sangre
4.
J Chem Phys ; 150(6): 064303, 2019 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-30769978

RESUMEN

The absolute photoabsorption cross sections for thiophene in the 5.0-10.7 eV range were measured using synchrotron radiation. New theoretical calculations performed at the time-dependent density functional theory level were used to qualitatively interpret the recorded photoabsorption spectrum. The calculations facilitated a re-analysis of the observed vibronic and Rydberg structures in the photoabsorption spectrum. Here a number of features have been re-assigned, while a number of other features have been assigned for the first time. This represents the most comprehensive and self-consistent assignment of the thiophene high-resolution photoabsorption spectrum to date.

5.
J Chem Phys ; 151(18): 184302, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31731857

RESUMEN

We present a comprehensive revisited experimental high-resolution vacuum ultraviolet (VUV) photoabsorption spectrum of ammonia, NH3, covering for the first time the full 5.4-10.8 eV energy-range, with absolute cross sections determined. The calculations on the vertical excitation energies and oscillator strengths were performed using the equation-of-motion coupled cluster method restricted to single and double excitation levels and used to help reanalyze the observed Rydberg structures in the photoabsorption spectrum. The VUV spectrum reveals several new features that are not previously reported in the literature, with particular reference to the vibrational progressions of the (D̃1E'←X̃1A1 '), the (F̃1E'←X̃1A1 '), and the (G̃1A2 ″←X̃1A1 ') absorption bands. In addition, new Rydberg members have been identified in nda1 '←1a2 ″D̃''1A2 ″←X̃1A1 ', where n > 3 has not been reported before as well as in nde″←1a2 ″F̃1E'←X̃1A1 ' and in nsa1 '←1a2 ″G̃1A2 ″←X̃1A1 '. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of ammonia in the Earth's atmosphere (0-50 km).

6.
Arch Gynecol Obstet ; 299(3): 835-840, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30607596

RESUMEN

PURPOSE: This article investigates the qualities and thermal effects of a novel electrosurgical device (PT) which has been designed by ERBE Elektromedizin GmbH, Germany, for the preparation of critical locations such as in skin-sparing or nipple-sparing techniques and compares it to a standard device (SD) in a porcine ex vivo breast model using an heat map generated by infrared thermography. METHODS: In total, 42 abdominal wall specimens of porcine tissue consisting of the skin and the underlying subcutaneous and muscle layer were alternately dissected using one of the devices and pre-settings. During the preparation with the two devices, the epicutaneous temperature was measured by an infrared camera (VarioCam, Jenoptik, Germany) and the maximum temperature as well as the slope of the temperature rise was analysed. RESULTS: The use of PT shows significantly lower values for [Formula: see text] compared to SD. This effect was independent from the chosen mode. Using the same instrument in different modes, the use of AutoCut mode showed a significant reduction of [Formula: see text] at all indicated time points (SD: p < 0.0001 and PT: p < 0.0001). In summary, the combination of AutoCut + PT showed the lowest rise in temperature, whereas the combination of DryCut + SD led to the highest rise in temperature. The temperature difference between these two settings was 13.84 °C, which means a possible temperature reduction of 67% can be achieved by the right choice of device and its tailored mode. CONCLUSIONS: The novel PT shows a significant reduction in epicutaneous temperature and a significant reduction of the slope of temperature rise most probably by a more focused application of energy compared to SD.


Asunto(s)
Mama/cirugía , Electrocirugia/métodos , Termografía/métodos , Animales , Mama/patología , Modelos Animales de Enfermedad , Femenino , Porcinos
7.
J Phys Chem A ; 122(41): 8191-8197, 2018 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-30231614

RESUMEN

We report a combined experimental and theoretical study of the electronic state spectroscopy of acrylic acid (C3H4O2) in the gas phase, by high-resolution vacuum ultraviolet (VUV) photoabsorption measurements in the 4.0-10.8 eV energy range, together with ab initio calculations (vertical energies and oscillator strengths), which were used in the assignment of the valence transitions. We also discuss the Rydberg transitions for this molecular target, obtained using the experimental ionization energies available in the literature. The experimental spectrum presented in this paper represents the highest resolution data yet reported for acrylic acid and reveals new features not previously reported in the literature. The dominant transitions have been assigned to (π*(4a″) ← π(3a″)) and (π*(4a″) ← π(2a″)), the latter exhibiting excitation of the ν5'( a') C = O stretching mode with mean energy of 0.155 eV. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of acrylic acid in the upper stratosphere (20-50 km).

8.
J Clin Monit Comput ; 32(5): 817-823, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29204771

RESUMEN

The aim of this study was to evaluate the accuracy and precision of non-invasive continuous blood pressure measurement by applanation tonometry (AT) in awake or anaesthetised cardiological intensive care patients. Patients suffering from highly impaired left ventricular function atrial fibrillation or severe aortic valve stenosis were included into the study. Arterial blood pressure was recorded by applanation tonometry (T-Line 400, Tensys Medical®, USA) and an arterial line in awake or anaesthetised patients. Discrepancies in mean (MAP), systolic (SAP), and diastolic (DAP) arterial pressure between the two methods were assessed as bias, limits of agreement and percentage error respectively. In 31 patients a total of 27,900 measurements were analyzed. The concordance correlation coefficient was 0.23, 0.45 and 0.06 for MAP, SAP and DAP, respectively. For all patients bias for MAPAT compared to MAPAL was 14.96 mmHg (SAPAT 4.51 mmHg; DAPAT 19.12 mmHg) with limits of agreement for MAPAT of 46.25 and - 16.33 mm Hg (SAPAT 48.00 and - 38.98 mmHg; DAPAT 50.12 and - 11.89 mmHg). Percentage error for MAPAT was 56.8% (42.7% for SAPAT; 75.2% for DAPAT). We conclude that the AT method is not reliable in ICU patients with severe cardiac comorbidities.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Monitorización Hemodinámica/métodos , Manometría/métodos , Anciano , Estenosis de la Válvula Aórtica/fisiopatología , Presión Arterial/fisiología , Fibrilación Atrial/fisiopatología , Determinación de la Presión Sanguínea/estadística & datos numéricos , Unidades de Cuidados Coronarios , Cuidados Críticos , Femenino , Monitorización Hemodinámica/estadística & datos numéricos , Humanos , Masculino , Manometría/estadística & datos numéricos , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Disfunción Ventricular Izquierda/fisiopatología , Análisis de Ondículas
9.
Phys Rev Lett ; 118(10): 109902, 2017 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-28339278

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.115.203902.

10.
Phys Chem Chem Phys ; 19(2): 1560-1570, 2017 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-27990546

RESUMEN

Hydronium ions produced by photolysis of water are used to study the protonation dynamics of alanine zwitterions in water. The measurements are done by UV-VIS and UV-IR femtosecond transient absorption spectroscopy on alanine in H2O and D2O. It is estimated that the reaction rate constant for the deuteration of alanine zwitterions is 4 × 1010 M-1 s-1, while the reverse process has a rate constant of 2 × 108 s-1. In addition to hydronium ions the photolysis of water yields hydrogen atoms and hydrated electrons together with hydroxyl radicals and hydroxyl ions. However, no other products resulting from reactions between aqueous alanine and the photolysis products of water are positively identified during the first 530 ps after the photolysis. Potential secondary reactions that are not observed experimentally are discussed and an upper limit is set for their yield where possible.

11.
Soft Matter ; 12(2): 373-7, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26472087

RESUMEN

The charge of a peptide influences final assembled structures. It is important to consider not only global charge, but also local, such as that found on the terminal residues. This work investigates the change of peptide self-assembly through the selection of different amino acid sequences and by varying the local charge of the residues on the C- and N-termini.

12.
Nanotechnology ; 27(30): 304001, 2016 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-27302044

RESUMEN

A wide variety of inorganic nanomaterials have been exploited so far for their great potential for biological applications. Some of these materials could be valid candidates to modulate the assembly of amyloid peptides, which is relevant to amyloid-related diseases. In this work, we reveal that a carbon nanomaterial can indeed modulate the assembly of amyloid peptides and, additionally, we show that this modulating effect is closely related to the dimensionality of the nanomaterials.


Asunto(s)
Nanoestructuras , Amiloide , Carbono , Péptidos
13.
J Phys Chem A ; 120(45): 8998-9007, 2016 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-27766869

RESUMEN

Here we report novel comprehensive investigations on the electronic state spectroscopies of isolated 2,4- and 2,6-difluorotoluene in the gas phase by high-resolution vacuum ultraviolet (VUV) photoabsorption measurements in the 4.4-10.8 eV energy range, with absolute cross-section values derived. We also present the first set of ab initio calculations (vertical energies and oscillator strengths), which we have used in the assignment of valence transitions of the difluorotoluene molecules, together with calculated ionization energies to obtain the Rydberg transitions for both molecules. The measured absolute photoabsorption cross sections have been used to estimate the photolysis lifetimes of 2,4- and 2,6-difluorotoluene in the Earth's atmosphere.

14.
J Chem Phys ; 145(3): 034302, 2016 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-27448882

RESUMEN

We present the experimental high-resolution vacuum ultraviolet (VUV) photoabsorption spectra of phenol covering for the first time the full 4.3-10.8 eV energy-range, with absolute cross sections determined. Theoretical calculations on the vertical excitation energies and oscillator strengths were performed using time-dependent density functional theory and the equation-of-motion coupled cluster method restricted to single and double excitations level. These have been used in the assignment of valence and Rydberg transitions of the phenol molecule. The VUV spectrum reveals several new features not previously reported in the literature, with particular reference to the 6.401 eV transition, which is here assigned to the 3sσ/σ(∗)(OH)←3π(3a″) transition. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of phenol in the earth's atmosphere (0-50 km).

15.
Klin Padiatr ; 228(2): 55-61, 2016 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-26697739

RESUMEN

Overweight and obesity in children and adolescents is a growing problem with an increasing number of patients presenting with comorbidities to pediatricians and orthopedic surgeons. This overview summarizes the most common orthopedic problems in overweight children and obesity and highlights the treatment options in addition to weight reduction and physiotherapy leaded activation. In early infancy a persitent genu varum may be seen as a sign of Blount disease. In the school ages flat feet or persistent knock-knees has a higher incidence in overweight children. The incidence for back pain and osteoporosis are related with overweight and obese. At puberty, the slipped capital epiphysis, which always needs a surgical management, is mostly related to overweight/obese. A symptomatic retroversion of the femur can cause discomfort and lead to a surgical therapy himself.


Asunto(s)
Enfermedades Musculoesqueléticas/etiología , Sobrepeso/complicaciones , Obesidad Infantil/complicaciones , Adolescente , Niño , Preescolar , Estudios Transversales , Femenino , Alemania , Humanos , Lactante , Masculino , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/terapia , Sobrepeso/epidemiología , Sobrepeso/terapia , Obesidad Infantil/epidemiología , Obesidad Infantil/terapia
16.
Phys Rev Lett ; 115(20): 203902, 2015 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-26613440

RESUMEN

We study the propagation of hard x rays in single curved x-ray waveguide channels and observe waveguide effects down to surprisingly small radii of curvature R≃10 mm and a large contour length s≃5 mm, deflecting beams up to 30°. At these high angles, about 2 orders of magnitude above the critical angle of total reflection θ(c), most radiation modes are lost by "leaking" into the cladding, while certain "survivor" modes persist. This may open up a new form of integrated x-ray optics "on a chip," requiring curvatures mostly well below the extreme values studied here, e.g., to split and to delay x-ray pulses.

17.
J Phys Chem A ; 119(34): 9059-69, 2015 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-26244250

RESUMEN

The electronic spectroscopy of isolated toluene in the gas phase has been investigated using high-resolution photoabsorption spectroscopy in the 4.0-10.8 eV energy range, with absolute cross-section measurements derived. We present the first set of ab initio calculations (vertical energies and oscillator strengths), which we use in the assignment of valence and Rydberg transitions of the toluene molecule. The spectrum reveals several new features not previously reported in the literature, with particular relevance to 7.989 and 8.958 eV, which are here tentatively assigned to the π*(17a') ← σ(15a') and 1π*(10a″) ← 1π(14a') transitions, respectively. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of toluene in the upper stratosphere (20-50 km).


Asunto(s)
Electrones , Teoría Cuántica , Sincrotrones , Tolueno/química , Rayos Ultravioleta , Absorción de Radiación , Atmósfera , Fotólisis , Espectrofotometría Ultravioleta , Vacio
18.
J Phys Chem A ; 119(32): 8647-56, 2015 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-26176891

RESUMEN

The highest resolution vacuum ultraviolet photoabsorption spectrum of isobutyl formate, C5H10O2, yet reported is presented over the energy range 4.5-10.7 eV (275.5-118.0 nm) revealing several new spectral features. Valence and Rydberg transitions and their associated vibronic series observed in the photoabsorption spectrum have been assigned in accordance with new ab initio calculations of the vertical excitation energies and oscillator strengths. Calculations have also been carried out to determine the ionization energies and fine structure of the lowest ionic state of isobutyl formate and are compared with a newly recorded photoelectron spectrum (from 9.0 to 27.0 eV). The value of the first ionization energy was determined to be 10.508 eV (adiabatic) and 10.837 eV (vertical). New vibrational structure is observed in the first photoelectron band, predominantly resulting from C-O and C═O stretches of the molecule. The photoabsorption cross sections have been used to calculate the photolysis lifetime of isobutyl formate in the upper stratosphere (20-50 km), indicating that the hydroxyl radical processes will be the main loss process for isobutyl formate.


Asunto(s)
Formiatos/química , Modelos Químicos , Espectroscopía de Fotoelectrones , Espectrofotometría Ultravioleta , Iones/química , Vacio , Vibración
19.
J Phys Chem A ; 119(31): 8503-11, 2015 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-26171941

RESUMEN

We present the first set of ab initio calculations (vertical energies and oscillator strengths) of the valence and Rydberg transitions of the anaesthetic compound halothane (CF3CHBrCl). These results are complemented by high-resolution vacuum ultraviolet photoabsorption measurements over the wavelength range 115-310 nm (10.8-4.0 eV). The spectrum reveals several new features that were not previously reported in the literature. Spin-orbit effects have been considered in the calculations for the lowest-lying states, allowing us to explain the broad nature of the 6.1 and 7.5 eV absorption bands assigned to σ*(C-Br) ← nBr and σ*(C-Cl) ← n(Cl) transitions. Novel absolute photoabsorption cross sections from electron scattering data were derived in the 4.0-40.0 eV range. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of halothane in the upper stratosphere (20-50 km).


Asunto(s)
Electrones , Halotano/química , Teoría Cuántica , Rayos Ultravioleta , Espectroscopía de Fotoelectrones , Sincrotrones , Vacio
20.
J Chem Phys ; 142(6): 064303, 2015 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-25681902

RESUMEN

The electronic state spectroscopy of carbonyl sulphide, COS, has been investigated using high resolution vacuum ultraviolet photoabsorption spectroscopy and electron energy loss spectroscopy in the energy range of 4.0-10.8 eV. The spectrum reveals several new features not previously reported in the literature. Vibronic structure has been observed, notably in the low energy absorption dipole forbidden band assigned to the (4π←3π) ((1)Δ←(1)Σ(+)) transition, with a new weak transition assigned to ((1)Σ(-)←(1)Σ(+)) reported here for the first time. The absolute optical oscillator strengths are determined for ground state to (1)Σ(+) and (1)Π transitions. Based on our recent measurements of differential cross sections for the optically allowed ((1)Σ(+) and (1)Π) transitions of COS by electron impact, the optical oscillator strength f0 value and integral cross sections (ICSs) are derived by applying a generalized oscillator strength analysis. Subsequently, ICSs predicted by the scaling are confirmed down to 60 eV in the intermediate energy region. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of carbonyl sulphide in the upper stratosphere (20-50 km).

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