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Dispositivos de insuflación-exsuflación en el fracaso respiratorio postoperatorio: informe de caso
No full textResumenIntroducciónEl padecimiento de una enfermedad neuromuscular es un factor predictor independiente de insuficiencia respiratoria postoperatoria. Esta complicación en ocasiones no responde al tratamiento con ventilación mecánica no invasiva.Presentación del casoManejo perioperatorio de un paciente con enfermedad de Werdnig-Hoffmann que fue intervenido de coronoidectomía bilateral por trismus. Su evolución postoperatoria se vio dificultada por la mala mecánica respiratoria del paciente que favoreció la aparición de atelectasias. A pesar de la aplicación de ventilación mecánica no invasiva de forma preventiva, el paciente terminó sufriendo insuficiencia respiratoria y requiriendo intubación orotraqueal. Finalmente se logra el destete respiratorio tras la aplicación de dispositivos de insuflación-exsuflación asociados a la ventilación mecánica no invasiva.ConclusiónLa aplicación de los dispositivos de insuflación-exsuflación en el postoperatorio inmediato de pacientes con enfermedades neuromusculares favorece la adecuada evolución respiratoria de un paciente considerado inicialmente como imposible de extubar.AbstractIntroductionPatients suffering from a neuromuscular disease have a greater likelihood of postoperative respiratory failure. Sometimes, this complication does not respond to non-invasive mechanical ventilation.Case reportPerioperative management of a patient with Werdnig-Hoffmann disease who underwent bilateral coronoidectomy due to trismus. The postoperative period was hampered by the patient's poor respiratory mechanics, inducing the appearance of atelectasis. Despite the application of preventive non-invasive mechanical ventilation, the patient suffered respiratory failure and required endotracheal intubation. Finally, the respiratory weaning was achieved after the application of insufflation-exsufflation devices associated with non-invasive mechanical ventilation.ConclusionThe application of insufflations-exsufflation devices in the immediate post-operative period of patients with neuromuscular diseases promotes the proper respiratory evolution of a patient considered impossible to extubate
Flow characteristics of various three-dimensional rounded contour bumps in a Mach 1.3 freestream
No full textAbstractStreamwise and spanwise flow pattern over three rounded contour bumps with different flow control strategies employed have been experimentally investigated in a Mach 1.3 freestream. Surface oil flow visualisation, Schlieren photography and particle image velocimetry measurements were used for flow diagnostics. Experimental data showed that in a Mach 1.3 freestream over the baseline plain bump, significant flow separation appeared at the bump crest that led to the formation of a large wake region downstream. In addition, two large counter-rotating spanwise vortices were formed in the bump valley. It was observed that the use of the passive by-pass blowing jet in the bump valley showed no obvious effects in reducing the sizes of both the wake region and the spanwise vortices in the bump valley. In contrast, it was found that the size of the wake region and the spanwise vortices could be reduced by blowing sonic jet in the bump valley. This approach of flow control found to be the most effective when the total pressure of the blowing jet was 2bar. It is deduced that the active blowing jet hindered the formation of the spanwise vortices in the bump valley as well as deflected the shear layer downwards so that a smaller re-circulating bubble was formed downstream of the bump crest
Mapping monthly rainfall erosivity in Europe
No full textAbstractRainfall erosivity as a dynamic factor of soil loss by water erosion is modelled intra-annually for the first time at European scale. The development of Rainfall Erosivity Database at European Scale (REDES) and its 2015 update with the extension to monthly component allowed to develop monthly and seasonal R-factor maps and assess rainfall erosivity both spatially and temporally. During winter months, significant rainfall erosivity is present only in part of the Mediterranean countries. A sudden increase of erosivity occurs in major part of European Union (except Mediterranean basin, western part of Britain and Ireland) in May and the highest values are registered during summer months. Starting from September, R-factor has a decreasing trend. The mean rainfall erosivity in summer is almost 4 times higher (315MJmmha−1h−1) compared to winter (87MJmmha−1h−1).The Cubist model has been selected among various statistical models to perform the spatial interpolation due to its excellent performance, ability to model non-linearity and interpretability. The monthly prediction is an order more difficult than the annual one as it is limited by the number of covariates and, for consistency, the sum of all months has to be close to annual erosivity. The performance of the Cubist models proved to be generally high, resulting in R2 values between 0.40 and 0.64 in cross-validation. The obtained months show an increasing trend of erosivity occurring from winter to summer starting from western to Eastern Europe. The maps also show a clear delineation of areas with different erosivity seasonal patterns, whose spatial outline was evidenced by cluster analysis. The monthly erosivity maps can be used to develop composite indicators that map both intra-annual variability and concentration of erosive events. Consequently, spatio-temporal mapping of rainfall erosivity permits to identify the months and the areas with highest risk of soil loss where conservation measures should be applied in different seasons of the year
Implementación de Avogadro como visualizador y constructor de moléculas para alumnos de primer año de Odontología en la asignatura Química General y Orgánica
No full textResumenLos visualizadores moleculares son hoy una realidad cada vez más presente en el aula, que permite a los estudiantes desarrollar habilidades de espaciamiento tridimensional de moléculas. Es por esto que en este estudio se utilizó el visualizador molecular Avogadro de libre acceso. El programa no solo permitió que los estudiantes se entrenaran en el desarrollo de la capacidad tridimensional, sino que también lograron asignar más rápidamente la quiralidad de carbonos en moléculas con isómeros ópticos. De hecho, la velocidad de asignación se redujo a la mitad comparada con moléculas bidimensionales. Por otro lado, se concluye que los alumnos son proclives a usar este programa no solo en cursos de química, sino en otros más avanzados.AbstractToday, molecular viewers are an undeniable reality in the classroom. This type of softwares allow students the 3 dimensional development. In this study, free access molecular viewer Avogadro was used. The using of the program was successful not only in the 3 dimensional training, but in the pointing out of carbons’ quilarity of optical isomers. In fact, the velocity was reduced to a half part in comparison to bidimensional molecules. On the other hand, students were prone to the usage of Avogadro in basic and advanced chemical courses
Some physico-chemical properties and catalytic activity of sulfate ion supported on WO3/SnO2 catalyst
No full textAbstractSolid acid catalyst 15wt%WO3/SnO2 was synthesized and loaded with 15wt%SO4. The obtained catalyst was calcined at 400, 500, 650 and 800°C. The prepared catalysts were characterized by TG-DTA, XRD, FTIR and N2 adsorption at −196°C. The surface acidity was measured by non aqueous potentiometric titration and FT-IR spectra of chemisorbed pyridine. The catalytic performance was evaluated on the esterification of propionic acid with n-butanol in liquid phase. The TG-DTA analysis shows that the decomposition of sulfate species occurred at >500°C. XRD measurements showed that WO3 dispersed completely on the surface of SnO2 and that the sulfating of WO3/SnO2 tends to hinder the crystallization of SnO2. The specific surface area, total pore volume and micropore volume are increased with increasing thermal treatment up to 500°C, and then decreased gradually with a further increase in calcination temperature. The prepared catalysts possess very strong acid sites and contain both Brønsted and Lewis acid sites. The total surface acidity decreased with raising of the calcination temperature. The highest conversion of propionic acid was for 400°C product, and decreased with an increase in calcination temperature. The effect of the reaction parameters, i.e., time of reaction, reaction temperature, and reactant molar ratio and the weight of the catalyst were also studied. The reaction obeys the second order kinetic equation with respect to propionic acid concentration. Brønsted and Lewis acid sites appeared to be needed for catalytic activity in n-butyl propionate formation
White blood cell count and new-onset atrial fibrillation after cardiac surgery
No full textAbstractBackgroundPostoperative new-onset atrial fibrillation (PNAF) is the most common complication following cardiac surgery. The inflammatory response, as a potential underlying mechanism, has been extensively studied. In small studies, the white blood cell count (WBC) has been shown to be the only consistent inflammatory marker associated with PNAF. This study aimed to determine the association between perioperative WBC response and PNAF in a larger study cohort.MethodsPatients ≥18years, undergoing elective cardiac surgery with a preoperative sinus rhythm were included. WBC was routinely measured preoperatively, and daily during the first four postoperative days. Main outcomes were the difference between peak postoperative WBC and neutrophil/lymphocyte ratio (N/L ratio) and preoperative WBC and N/L ratio (ΔWBC and ΔN/L ratio respectively). Development of PNAF was evaluated in all patients with continuous 12-lead ECG monitoring.Results657 patients were included and 277 (42%) developed PNAF. Univariable analyses showed a statistically significant relationship between ΔWBC (P=0.030) and ΔN/L ratio (P=0.002), and PNAF. In multivariable analysis no significant relationship was found between ΔWBC (OR: 1.14 per 1×109/L increase; 95% CI: 0.65–2.03; P=0.645), ΔN/L ratio (OR: 1.65 per 1×109/L increase; 95% CI: 0.94–2.90; P=0.089), and PNAF. Increasing age (OR: 1.08 per year; 95% CI: 1.01–1.16; P=0.022) and (additional) valve surgery (versus CABG) (OR: 4.96; 95% CI: 2.07–6.91; P≤0.001) were associated with PNAF.ConclusionsThe perioperative WBC response and its components were not associated with the development of PNAF
Catastrophic metallosis after tumoral knee prosthesis failure: A case report
No full textAbstractIntroductionMetallosis is a condition characterized by an infiltration of periprosthetic soft tissues and bone by metallic debris resulting from wear or failure of joint arthroplasties.Presentation of caseAuthors describe a case of a 45-year-old man treated for an osteosarcoma of the distal femur with a modular prosthesis when he was 18 years old, he developed massive metallosis with skin dyspigmentation after 17 years. His medical\surgical history was remarkable for a left tumoral knee prosthesis implanted 21 years ago. Two years before revision, the patient had a car accident with a two-points prosthesis breakage and despite the surgeon’s advice, the patient refused surgery. In two years, prosthesis malfunction caused a progressive catastrophic soft tissues infiltration of metallic debris.Discussion and conclusionAuthors suggest that if prosthesis fracture is detected, revision surgery should be attempted as earlier as possible
Russian olive (Elaeagnus angustifolia L.): From a variety of traditional medicinal applications to its novel roles as active antioxidant, anti-inflammatory, anti-mutagenic and analgesic agent
No full textAbstractElaeagnus angustifolia L., which is commonly known as oleaster or Russian olive, is a deciduous plant from Elaeagnacea family. This plant can tolerate and survive a wide variety of environmental conditions. Different parts of E. angustifolia plant, especially the fruits and flowers, have been used traditionally in treating a variety of common illnesses such as nausea, cough, asthma, fever, jaundice, and diarrhea. The use of fruit powder and extract of E. angustifolia L. have shown to be effective in alleviating pain in patients with rheumatoid arthritis and also in reducing the healing time of wounds in injured person. In addition, some recent reports have indicated the anti-oxidant, anti-inflammatory, antimicrobial, anticancer and some other properties of oleaster plant. The other important property of this plant would be its role in bio-monitoring the environment for some toxic elements and also its action as a bio-fertilizer agent in distressed lands. It seems that with more advanced studies on E. angustifolia L. and its bioactive components, this plant might be potentially effective and can be used as a natural alternative resource in pharmaceutical industries for treating chronic and serious problems, Fig. 1
Enhanced MFC power production and struvite recovery by the addition of sea salts to urine
No full textAbstractUrine is an excellent fuel for electricity generation in Microbial Fuel Cells (MFCs), especially with practical implementations in mind. Moreover, urine has a high content in nutrients which can be easily recovered. Struvite (MgNH4PO4·6H2O) crystals naturally precipitate in urine, but this reaction can be enhanced by the introduction of additional magnesium. In this work, the effect of magnesium additives on the power output of the MFCs and on the catholyte generation is evaluated. Several magnesium sources including MgCl2, artificial sea water and a commercially available sea salts mixture for seawater preparation (SeaMix) were mixed with real fresh human urine in order to enhance struvite precipitation. The supernatant of each mixture was tested as a feedstock for the MFCs and it was evaluated in terms of power output and catholyte generation. The commercial SeaMix showed the best performance in terms of struvite precipitation, increasing the amount of struvite in the solid collected from 21% to 94%. Moreover, the SeaMix increased the maximum power performance of the MFCs by over 10% and it also changed the properties of the catholyte collected by increasing the pH, conductivity and the concentration of chloride ions. These results demonstrate that the addition of sea-salts to real urine is beneficial for both struvite recovery and electricity generation in MFCs
Marine anthropogenic litter on British beaches: A 10-year nationwide assessment using citizen science data
No full textAbstractGrowing evidence suggests that anthropogenic litter, particularly plastic, represents a highly pervasive and persistent threat to global marine ecosystems. Multinational research is progressing to characterise its sources, distribution and abundance so that interventions aimed at reducing future inputs and clearing extant litter can be developed. Citizen science projects, whereby members of the public gather information, offer a low-cost method of collecting large volumes of data with considerable temporal and spatial coverage. Furthermore, such projects raise awareness of environmental issues and can lead to positive changes in behaviours and attitudes. We present data collected over a decade (2005–2014 inclusive) by Marine Conservation Society (MCS) volunteers during beach litter surveys carried along the British coastline, with the aim of increasing knowledge on the composition, spatial distribution and temporal trends of coastal debris. Unlike many citizen science projects, the MCS beach litter survey programme gathers information on the number of volunteers, duration of surveys and distances covered. This comprehensive information provides an opportunity to standardise data for variation in sampling effort among surveys, enhancing the value of outputs and robustness of findings. We found that plastic is the main constituent of anthropogenic litter on British beaches and the majority of traceable items originate from land-based sources, such as public littering. We identify the coast of the Western English Channel and Celtic Sea as experiencing the highest relative litter levels. Increasing trends over the 10-year time period were detected for a number of individual item categories, yet no statistically significant change in total (effort-corrected) litter was detected. We discuss the limitations of the dataset and make recommendations for future work. The study demonstrates the value of citizen science data in providing insights that would otherwise not be possible due to logistical and financial constraints of running government-funded sampling programmes on such large scales