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1.
J Phys Chem Lett ; 14(26): 6061-6070, 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37358397

RESUMEN

XUV photoelectron spectroscopy (XPS) is a powerful method for investigating the electronic structures of molecules. However, the correct interpretation of results in the condensed phase requires theoretical models that account for solvation. Here we present experimental aqueous-phase XPS of two organic biomimetic molecular switches, NAIP and p-HDIOP. These switches are structurally similar, but have opposite charges and thus present a stringent benchmark for solvation models which need to reproduce the observed ΔeBE = 1.1 eV difference in electron binding energy compared to the 8 eV difference predicted in the gas phase. We present calculations using implicit and explicit solvent models. The latter employs the average solvent electrostatic configuration and free energy gradient (ASEC-FEG) approach. Both nonequilibrium polarizable continuum models and ASEC-FEG calculations give vertical binding energies in good agreement with the experiment for three different computational protocols. Counterions, explicitly accounted for in ASEC-FEG, contribute to the stabilization of molecular states and reduction of ΔeBE upon solvation.

2.
Artículo en Inglés | MEDLINE | ID: mdl-34444060

RESUMEN

Pandemics impose an immense psychological burden on healthcare workers due to a combination of workplace stressors and personal fears. Nurses and auxiliary nursing care technicians (ANCTs) are on the front line of this pandemic and form the largest group in healthcare practice. The aim of this study is to determine the symptoms of depression and/or anxiety among nurses and ANCTs during the periods known as the first wave (March-June) and second wave (September-November) of theCOVID-19 pandemic in Spain. An observational cross-sectional study was carried out using an anonymous, self-administered questionnaire among nurses and ANCTs practising in Spain. During the first period, 68.3% and 49.6% of the subjects presented anxiety and depression, respectively, decreasing in the second period (49.5% for anxiety and 35.1% for depression). There were statistically significant differences between the different categories and periods (p < 0.001). The COVID-19 pandemic has negatively influenced mental health in nurses and ANCTs. Mental health should be monitored and coping strategies promoted to improve the health, productivity and efficiency of these professionals.


Asunto(s)
COVID-19 , Salud Mental , Enfermeras y Enfermeros , Asistentes de Enfermería/psicología , Ansiedad/epidemiología , COVID-19/psicología , Estudios Transversales , Depresión/epidemiología , Personal de Salud , Humanos , Enfermeras y Enfermeros/psicología , Pandemias , Encuestas y Cuestionarios
3.
Intern Med J ; 45(11): 1173-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26010490

RESUMEN

BACKGROUND: Rhabdomyolysis (RB) is a syndrome characterised by decomposition of skeletal muscle that could be life threatening, so the identification of biomarkers of its severity could help us in its treatment. Creatine kinase (CK) is usually taken as a reference in patients with RB in order to stratify prognosis, however that is not probably the most effective parameter. AIMS: The present study was designed to analyse the specific features and mortality of patients with RB and the relation between creatinine, CK and mortality. METHODS: Retrospective cohort analysis among patients admitted to San Pedro Hospital in Logroño (Spain) with RB (CK levels higher than 2000 U/L) diagnosed since 1 January 2009 until 31 December 2; 013 522 patients with RB patients diagnosed of RB were collected. The aetiology and the analytical feature (creatinine, CK, calcium, phosphorus, pH and bicarbonate), as well as 30-year mortality, were investigated. RESULTS: Among the 522 patients, there were 138 deaths. Four patients required renal replacement therapy. The most common cause of RB was trauma (29%). Infectious aetiology had the highest mortality (41.2%). The median CK was 3451 u/L (interquartile range 3348), and the mean creatinine at admission was 132.6 umol/L (±110.5). Initial CK levels do not have predictive ability on mortality or renal dysfunction in contrast to initial creatinine values. Each state of acute kidney injury (AKI) increased mortality compared with those who have not presented this renal dysfunction (P < 0.0001). Age, calcium, phosphorus, bicarbonate and pH are associated with AKI. CONCLUSION: Despite being a diagnostic marker for RB, initial CK levels do not predict mortality. However, creatinine initial levels are related to progression to acute renal injury and mortality at 30 days.


Asunto(s)
Lesión Renal Aguda/mortalidad , Lesión Renal Aguda/orina , Creatinina/orina , Rabdomiólisis/mortalidad , Rabdomiólisis/orina , Lesión Renal Aguda/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/orina , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Rabdomiólisis/diagnóstico , España/epidemiología
4.
Ultrasonics ; 54(6): 1575-80, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24794506

RESUMEN

The progress of malolactic fermentation in red wines has been monitored by using ultrasonic techniques. The evolution of ultrasonic velocity of a tone burst 1MHz longitudinal wave was measured, analyzed and compared to those parameters of oenological interest obtained simultaneously by analytical methods. Semi-industrial tanks were used during measurements pretending to be in real industrial conditions. Results showed that the ultrasonic velocity mainly changes as a result of the conversion by lactic acid bacteria of malic acid into lactic acid and CO2. Overall, the present study has demonstrated the potential of the ultrasonic technique in monitoring the malolactic fermentation process.


Asunto(s)
Fermentación , Ácido Láctico/análisis , Malatos/análisis , Ultrasonido , Vino/análisis , Tecnología de Alimentos , Volatilización
6.
Ultrasonics ; 51(2): 223-8, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20875657

RESUMEN

In this work, the wheat flour properties are investigated using ultrasound techniques. Moreover, the flour samples were also characterized by means of well established techniques such as protein content, Alveograph and Mixolab®. A set of 35 dough samples, made of wheat flours with diverse physical and quality properties, were studied. The obtained results shown that ultrasound measurements can detect changes in the dough consistency induced by proteins and also by gelatinization of the starch. Furthermore, ultrasound measurements can be related to parameters indicative of the proteolytic degradation or softening of the dough due to protease activity. Thus, ultrasound can be considered a low cost and rapid tool, complementary to conventional test, for wheat flour characterization.


Asunto(s)
Harina , Triticum/química , Ultrasonido/métodos , Diseño de Equipo , Manipulación de Alimentos , España , Almidón/química
7.
Rev Gastroenterol Mex ; 73(3): 177-80, 2008.
Artículo en Español | MEDLINE | ID: mdl-19671507

RESUMEN

Meckel's diverticulum is an uncommon cause of acute abdominal pain in patients older than 85 years old. We present two female patients, older than 85 years old, treated surgicaly with symptomatic Meckel's diverticulum. This diagnosis wasn't suspected in a preoperative way in both cases. Complications of Meckel's diverticulum are rarely considered in the geriatric population.


Asunto(s)
Divertículo Ileal , Anciano de 80 o más Años , Femenino , Humanos , Divertículo Ileal/diagnóstico , Divertículo Ileal/cirugía
9.
Ultrasonics ; 46(3): 270-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17462688

RESUMEN

Within the baking industry, the control of dough properties is required to achieve final product quality and consistency. Traditional methods for dough testing are slow and off-line and do not provide fundamental rheological information. There is therefore a need for the development of fast and on-line instruments capable of providing relevant data for baking. Ultrasonics provide a non-destructive, rapid and low cost technique for the measurement of physical food characteristics. In this work, the water content of dough is investigated using ultrasonic techniques. The capability of ultrasound measurements for discriminating flours for different purposes is also studied. Doughs from more than 30 flours were characterised rheologically using a Chopin Alveograph and a Brabender Extensograph. Ultrasound measurements on the doughs prepared from these flours were also performed. The measurements were correlated, showing that ultrasound was an alternative measurement method to discriminate types of flours for different purposes.


Asunto(s)
Algoritmos , Harina/análisis , Análisis de los Alimentos/métodos , Interpretación de Imagen Asistida por Computador/métodos , Ultrasonografía/métodos , Agua/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Ultrasonics ; 44 Suppl 1: e1051-5, 2006 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-16797637

RESUMEN

The viscoelastic properties of dough are of great interest in the baking industry as they affect the quality of the final product. In this work, the viscoelastic properties of dough were investigated using ultrasonic techniques and then compared with traditional methods. It has been shown that ultrasonics provides a non-destructive, rapid and low cost technique for the measurement of physical food characteristics. A common protocol for dough preparation was used for each type of measurement. Experimental results on more than 30 different flour quality and dough processing were presented. The measurements were correlated and compared with traditional dough quality tests. In addition, the capability of ultrasound measurements for discriminating flours for different purposes was also studied, showing the potential of ultrasound as an alternative measurement method to discriminate types of flours for different purposes.


Asunto(s)
Harina/análisis , Análisis de los Alimentos/métodos , Manipulación de Alimentos/métodos , Interpretación de Imagen Asistida por Computador/métodos , Ensayo de Materiales/métodos , Ultrasonografía/métodos , Agua/química , Algoritmos , Elasticidad , Harina/clasificación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Viscosidad , Agua/análisis
11.
Ultrasonics ; 44 Suppl 1: e667-72, 2006 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-16797644

RESUMEN

Air coupled piezoelectric ultrasonic array transducers are a novel tool that could lead to interesting advances in the area of non-contact laminar material testing using Lamb wave's propagation techniques. A key issue on the development of such transducers is their efficient coupling to air media (impedance mismatch between the piezoelectric material and air is 90 dB or more). Adaptation layers are used in order to attain good matching and avoid possible serious signal degradation. However, the introduction of these matching layers modify the transducer surface behaviour and, consequently, radiation characteristics are altered, making the usual idealization criteria (of uniform surface movement) adopted for field simulation purposes inaccurate. In our system, we have a concave linear-array transducer of 64 elements (electrically coupled by pairs) working at 0.8 MHz made of PZ27 rectangular piezoceramics (15 mm x 0.3 mm) with two matching layers made of polyurethane and porous cellulose bonded on them. Experimental measurements of the acoustic aperture of single excited array elements have shown an increment on the geometrical dimensions of its active surface. A sub-millimeter vibrometer laser scan has revealed an extension of the aperture beyond the supposed physical single array element dimensions. Non-uniform symmetric apodized velocity surface vibration amplitude profile with a concave delay contour indicates the presumed existence of travelling wave phenomena over the surface of the outer array matching layer. Also, asymptotic propagation velocities around 2500 m/s and attenuation coefficient between 15 and 20 dB/mm has been determined for the travelling waves showing clear tendencies. Further comparisons between the experimental measurements of single array element field radiation diagram and simulated equivalent aperture counterpart reveal good agreement versus the ideal (uniform displaced) rectangular aperture. For this purpose an Impulse Response Method (IRM) has been used.

12.
Ultrasonics ; 44 Suppl 1: e1093-100, 2006 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-16797654

RESUMEN

This work presents an ultrasonic sensor for on-line batter monitoring with low-noise design considerations. The density and the compressibility of the batter vary as a function of mixing time and are strongly related to the quality of the final product. Traditionally, a batter sample of a fixed volume is removed and weighted in order to determine its density. This is a time consuming process. Benefits to the industry of on-line measuring techniques include better control of product quality, improving processing efficiencies and reduction in wastage. In this paper low-noise design considerations are accounted for an ultrasonic sensor based on a piezoceramic disk mounted between two reference buffer rods of acrylic resin to measure the acoustic impedance of the batter. Measuring the acoustic impedance changes of the batter its compressibility and density can be monitored. Spurious echoes generated at different parts of the buffer rods boundary strongly affect accuracy and reliability of the measurements, and are considered as noise. The influence of buffer rods geometry on noise level is studied using simulations and afterwards justified experimentally. Design aspects such as buffer rods length and radius, piezoceramic disk frequency and radius are discussed and their influence on noise level is shown. Finally, strategies for optimum geometry design of the ultrasonic sensor are given.


Asunto(s)
Diseño Asistido por Computadora , Análisis de los Alimentos/instrumentación , Interpretación de Imagen Asistida por Computador/métodos , Ensayo de Materiales/métodos , Modelos Teóricos , Transductores , Ultrasonografía/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Aumento de la Imagen/instrumentación , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ultrasonografía/métodos
13.
Chemistry ; 9(16): 3833-6, 2003 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-12916107

RESUMEN

A simple and convenient one-pot synthesis of THF solutions of high molecular weight poly(dichlorophosphazene) [NPCl(2)](n), or the (15)N isotopomer [(15)NPCl(2)](n), starting directly from PCl(5) and NH(4)Cl or (15)NH(4)Cl in a solution of 1,2,4-trichlorobenzene in the presence of sulfamic acid and calcium sulfate dihydrate, is described. The solutions of [NPCl(2)](n) in THF, which are obtained free of poly(tetrahydrofuran) by preparing them in the presence of K(2)CO(3), can be reacted directly with phenols, biphenols, or even HO-CH(2)CF(3) in the presence of K(2)CO(3) or Cs(2)CO(3) to obtain, after a very simple workup, the corresponding polyphosphazene derivatives almost free of chlorine.

14.
Chemistry ; 7(7): 1486-94, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11330903

RESUMEN

The structure and the assembly of tris-(2,2'-dioxy-binaphthyl)cyclotriphosphazene [(+)-[NP3(O2C20H12)3], DBNP, in the solid amorphous state was studied using molecular dynamics (MD) including ad hoc quantum mechanically derived force field (FF) parameters, in combination with the energy dispersive X-ray diffraction (EDXD) technique. The atom-atom radial distribution function (RDF) curve obtained through the EDXD experiment revealed low intensity peaks not attributable to the intramolecular distances of the single molecule, but clearly featuring a low energy state of long-distance three-dimensional assembly. The radial distribution functions (RDF) were calculated for various models of DBNP submitted to theoretical MD simulations. Based on the comparison of theoretically calculated RDFs and those obtained from the EDXD experiment, the predominant structural motif of the material in the bulk was found to have DBNP molecules laid one upon the other to form tubular nanostructures. These contain eight DBNP units each (length ca. 46 A) with two and three of these units aligned in parallel and held together. The material can be represented as a bulk of tubular snake-like chains undergoing distortions with a step of eight DBNP units. The bending angles, that vary randomly, attain limited values sufficient to induce disorder and thus nonperiodic structure. The present application of MD simulations combined with EDXD data appear to be a general approach to solve for the first time otherwise intractable issues concerning structural features and assembly of molecular materials in the bulk.

15.
Am J Respir Cell Mol Biol ; 24(5): 591-8, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11350829

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disorder characterized by fibroblast proliferation and extracellular matrix accumulation. However, studies on fibroblast growth rate and collagen synthesis have given contradictory results. Here we analyzed fibroblast growth rate by a formazan-based chromogenic assay; fibroblast apoptosis by in situ end labeling (ISEL) and propidium iodide staining; percent of alpha-smooth muscle actin (alpha-SMA) positive cells by fluorescence-activated cell sorter; and alpha1-(I) collagen, transforming growth factor (TGF)-beta1, collagenase-1, gelatinases A and B, and tissue inhibitor of metalloproteinase (TIMP)-1, -2, -3, and -4 expression by reverse transcriptase/polymerase chain reaction in fibroblasts derived from IPF and control lungs. Growth rate was significantly lower in IPF fibroblasts compared with controls (13.3 +/- 38.5% versus 294.6 +/- 57%, P < 0.0001 at 13 d). Conversely, a significantly higher percentage of apoptotic cells was observed in IPF-derived fibroblasts (ISEL: 31.9 +/- 7.0% versus 15.5 +/- 7.6% from controls; P < 0.008). alpha-SMA analysis revealed a significantly higher percentage of myofibroblasts in IPF samples (62.8 +/- 25.2% versus 14.8 +/- 11.7% from controls; P < 0.01). IPF fibroblasts were characterized by an increase in pro-alpha1-(I) collagen, TGF-beta1, gelatinase B, and all TIMPs' gene expression, whereas collagenase-1 and gelatinase A expression showed no differences. These results suggest that fibroblasts from IPF exhibit a profibrotic secretory phenotype, with lower growth rate and increased spontaneous apoptosis.


Asunto(s)
Apoptosis , Fibroblastos/metabolismo , Pulmón , Fibrosis Pulmonar/metabolismo , Inhibidores Tisulares de Metaloproteinasas/biosíntesis , División Celular , Células Cultivadas , Colágeno/genética , Colágeno/metabolismo , Femenino , Fibroblastos/patología , Perfilación de la Expresión Génica , Humanos , Masculino , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Persona de Mediana Edad , Fibrosis Pulmonar/patología , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Inhibidores Tisulares de Metaloproteinasas/genética , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta1
16.
Environ Sci Technol ; 35(7): 1289-93, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11348058

RESUMEN

Certain volcanoes constitute the world's largest sources of SO2, HCl, and HF emissions and contribute significantly to regional acid deposition. However, the impact of volcanic acid emissions to nearby ecosystems remain poorly documented. In this paper, the spatial pattern of acid dry depositions was monitored within 44 km of Masaya Volcano, Nicaragua, with a network of sulfation plates. Measured SO2 deposition rates were <2-791 mg m(-2) day(-1). The plates also collected the dry deposition of HCI at rates of <1-297 mg m(-2) day(-1). A similar deposition velocity Vd (gas transfer) of 1.6 +/- 0.8 cm/s was calculated for SO2 and HCl above the plate surfaces. Quantities of SO2 and HCI deposited daily within the area surveyed amounted to 1.5 x 10(8) g and 5.7 x 10(7) g, respectively, which correspond to about 10% of the total SO2 and HCl released by the volcano. These depositions may generate an equivalent hydrogen flux ranging from <1 to 30 mg m(-2) day(-1). Our results demonstrate that volcano emissions can dramatically affect acid deposition downwind and in turn cause extreme acid loading of the local ecosystems. This study opens exciting prospects for investigating the sensivity of volcanic ash soils to acid inputs.


Asunto(s)
Lluvia Ácida , Ácido Clorhídrico/análisis , Dióxido de Azufre/análisis , Erupciones Volcánicas , Movimientos del Aire , Ecosistema , Monitoreo del Ambiente , Hidrógeno/química , Nicaragua
17.
Gastroenterol Hepatol ; 23(3): 109-15, 2000 Mar.
Artículo en Español | MEDLINE | ID: mdl-10804686

RESUMEN

AIM: To analyze our experience in self-training in needle-knife sphincterotomy and to estimate the number of procedures necessary to reach competence in this technique. METHOD: Retrospective analysis of the first 60 needle-knife sphincterotomies performed, paying attention to success rates, the need for one or two attempts and the incidence and severity of early complications. The results were analyzed and divided into 2-year periods. The training period was subsequently determined using a qualitative method which combines the three above-mentioned criteria and sets competence level at 90%. RESULTS: Of the 60 attempted needle-knife sphincterotomies (five in Billroth-II patients), 54 (90%) were completed. The procedure was required in 20% of all the sphincterotomies completed. Needle-knife sphincterotomy was completed at the first attempt in 39 (65%) patients and complications appeared in 13 (22%), three (5%) of which were serious but not fatal. Analysis of 2 year periods showed an almost 100% increase in the total number of needle-knife sphincterotomies completed and in those completed at the first attempt, as well as a reduction in the complication rate, which subsequently stabilized at below 15%. Forty needle-knife sphincterotomies were needed to reach competence level. CONCLUSION: Needle-knife sphincterotomy can be learned without training from an endoscopist with experience in this technique. Competence can be reached after 40 procedures. Nevertheless, we propose an alternative method to our own to achieve competence in less time and with fewer complications.


Asunto(s)
Cirugía General/educación , Esfinterotomía Endoscópica/métodos , Competencia Clínica/estadística & datos numéricos , Cirugía General/estadística & datos numéricos , Humanos , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Esfinterotomía Endoscópica/instrumentación , Esfinterotomía Endoscópica/estadística & datos numéricos , Resultado del Tratamiento
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