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Summary Purpose To report predictive factors for therapeutic response to anti-VEGF in patients with neovascular age-related macular degeneration (nAMD) in daily clinical practice in our patient population. Methods Retrospective cohort study including 56 patients (69 eyes) with nAMD treated with anti-VEGF, followed for at least two years between February 2012 and April 2018. Patients received three intravitreal anti-VEGF (bevacizumab) injections (loading dose) and were monitored and treated according to a PRN regimen. We analysed whether a gain in visual acuity of 15 or more ETDRS letters at the final visit was associated with demographic characteristics, presence of systemic comorbidities, fundus lesions or measurable improvement on Cirrus optical coherence tomography (OCT) between the first and last visit. Results After a mean follow-up of 15.5 months (4.7–27.8 interquartile range), central retinal thickness (CRT) (RR: 1.004; IC 95%: 1.001–1.007; P = 0.011) and macular hemorrhage (RR: 0.30; IC 95%: 0.10–0.90, P = 0.032) at baseline were found to be useful predictive factors for visual acuity improvement (≥ 15 letters) in patients treated for nAMD by anti-VEGF in a real world clinical setting. Conclusion In the present series of patients with nAMD receiving a loading dose of bevacizumab and followed according to a PRN regimen for 24 months, the only predictable factors for a ≥ 15 letter gain in visual acuity were anatomical response as measured by OCT and macular hemorrhage at baseline.

Aircraft turbulence is one of the most dangerous meteorological phenomena that can affect aviation safety. This study is focused on the turbulence associated to mountain lee waves in the vicinity of Adolfo Suárez Madrid-Barajas airport (Spain). Sixty-eight mountain lee waves events are selected to simulate the turbulence with the Weather Research and Forecasting (WRF-ARW) and the HARMONIE-AROME numerical weather prediction models. To study and characterize the turbulence associated, the vertical wind speeds are selected as an important variable and the Eddy Dissipation Rate is estimated. Both models have properly simulated the turbulence and the clear air turbulence, obtaining higher values of turbulence intensity by WRF-ARW than HARMONIE-AROME in the mountain lee waves events. Finally, these results are used to enhance a mountain wave warning decision tree, including the turbulence warning which is validated through several turbulence reports.

Aim To describe the efficacy of a modification of the superior inverted flap technique, with maculorrhexis, in vitrectomy for full-thickness macular hole (MH) surgery compared to internal limiting membrane peeling (ILM). Methods Retrospective and comparative study of patients with MH. In group A, a superior ILM flap is created to cover the macular hole, and in group B conventional ILM peeling was performed. Results A total of 80 eyes were included (44 group A and 36 group B). MH closure occurred in 100% in group A and 91.67% in group B (p = 0.0869). There were more U-type closures in group A(90.91%) than in group B(58.33%), p = 0.0017. Both groups showed Best corrected visual acuity (BCVA) improvement at 3 and 6 months. At 3 months BCVA in group A was significantly better but at 6 months results were similar. Ellipsoid layer (EZ) recovery at 6 months was achieved in 81.82% patients in group A and 52.78% in B (p = 0.005), and external limiting membrane in 81.82% in group A and 69.44% in B (p = 0.1957). Conclusions The superior inverted flap maculorrhexis technique is suitable for idiopathic MH treatment, with better anatomical and non-inferior functional results than the classic ILM peeling. It achieves functional recoveries earlier, better BCVA and greater gains at 3 months compared to the classic ILM peeling. It also obtains a higher number of U-shaped closures and higher EZ restorations.

Producción Científica, ERA5 represents the state of the art for atmospheric reanalyses and is widely used in meteorological and climatological research. In this work, this dataset is evaluated using the wind kinetic energy spectrum. Seasonal climatologies are generated for 30° latitudinal bands in the Northern Hemisphere (periodic domain) and over the North Atlantic area (limited-area domain). The spectra are also assessed to determine the effective resolution of the reanalysis. The results present notable differences between the latitudinal domains, indicating that ERA5 is properly capturing the synoptic conditions. The seasonal variability is adequate too, being winter the most energetic, and summer the least energetic season. The limited area domain results introduce a larger energy density and range. Despite the good results for the synoptic scales, the reanalysis’ spectra are not able to properly reproduce the dissipation rates at mesoscale. This is a source of uncertainties which needs to be taken into account when using the dataset. Finally, a cyclone tropical transition is presented as a case study. The spectrum generated shows a clear difference in energy density at every wavelength, as expected for a highly-energetic status of the atmosphere., Ministerio de Asuntos Económicos y Transformación Digital y Universidad Complutense de Madrid (projects: (PID2019-105306RB-I00 (IBER - CANES), CGL2016-78702 (SAFEFLIGHT), PCIN-2016-080 and FEI-EU-17-16), Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCLE

To determine corneal topographic, anatomic, and biomechanical properties in patients newly diagnosed with severe obstructive sleep apnea-hypopnea syndrome (OSAHS).This is a cross-sectional study including 25 patients recently diagnosed with severe OSAHS (apnea-hypopnea index above 30) and a paired control group of 25 healthy subjects. All patients underwent a complete eye examination with an elevation topography Pentacam Scheimpflug study and a study with Reichert Ocular Response Analyzer, collecting several topographic, anatomic, and biomechanical variables.Fifty eyes of 25 patients (23 of them were men) diagnosed with OSAHS by somnography and the same number of healthy subjects (23 of them were men) were included, with an average age of 64 ± 11 years (range 45-78 years) for cases and an average age of 64 ± 11 years (range 45-81 years) for the controls. No differences were found in keratometry, cylinder, refractive indexes, Bad-D, or pachymetry. The mean corneal volume for cases was 58.64 ± 3.05 mm and for the controls 60.48 ± 3.33 mm (P = 0.005). The mean minimum radius for cases was 7.49 ± 0.31 and for the controls 7.36 ± 0.30 (P = 0.035). The mean elevation in apex for cases was 8.46 ± 5.18 and for the controls 2.38 ± 2.36 (P ≤ 0.001). Two eyes with a topographic diagnosis of keratoconus (KC) and another 6 with subclinical KC were detected using the Pentacam in the OSAHS group.Many of the corneal topographic and biomechanical variables in patients with severe OSAHS present different values from the general population with a trend toward KC values, such as keratoconus index or paired keratoconus index. Compared with the control group, significant differences were found in corneal volume, corneal elevation, and minimum radius.

Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis. It strengthens the ARIA change management strategy in the prevention and management of airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical framework, solutions for practical steps of digital enhancement of care are proposed.

A retinal pigment epithelial (RPE) tear is a well-known complication of retinal pigment epithelial detachments (PED) and may cause a significant visual impairment. The most common cause is a vascularized PED in patients with exudative age-related macular degeneration (AMD). The development of diagnostic imaging techniques brings us closer to the etiology and pathophysiological mechanisms of this entity, offering us new strategies for treatment and follow-up. The advent of intravitreal antiangiogenic treatment (anti-VEGF) has led to an increase in the number of reported cases of RPE tears, which are an important vision-limiting factor during treatment. However, RPE tears may occur spontaneously or as a consequence of thermal laser treatment, photodynamic therapy or anti-VEGF therapy. It is accepted that the mechanism of RPE tears is multifactorial. The optimization of the functional outcome of this complication has been described with continuous treatment with antiangiogenic drugs. The goal of the present review is to evaluate the incidence, risk factors and treatment of RPE tears.

Geographic atrophy is characterized by severe visual deficit whose etiology and pathophysiology are yet to be elucidated. As a working hypothesis, oxidative damage could trigger a chronic inflammation in Bruch's membrane-RPE-choriocapillaris complex, mostly due to complement pathway overactivation. Some individuals with mutations in the complement system and other factors have diminished capacity in the modulation of the inflammatory response, which results in cell damage and waste accumulation. This accumulation of intracellular and extracellular waste products manifests as drusen and pigmentary changes that precede the atrophy of photoreceptors, RPE, choriocapillaris with an ischemic process with decreased choroid flow. All these processes can be detected as tomographic findings and autofluorescence signals that are useful in the evaluation of patients with atrophic AMD, which helps to establish an individualized prognosis. Anti-inflammatory, antioxidant and therapies that decrease the accumulation of toxins for the preservation of the RPE cells and photoreceptors are being investigated in order to slow down the progression of this disease.

Aims: Mobile Airways Sentinel NetworK (MASK) belongs to the Fondation Partenariale MACVIA-LR of Montpellier, France and aims to provide an active and healthy life to rhinitis sufferers and to those with asthma multimorbidity across the life cycle, whatever their gender or socio-economic status, in order to reduce health and social inequities incurred by the disease and to improve the digital transformation of health and care. The ultimate goal is to change the management strategy in chronic diseases. Methods: MASK implements ICT technologies for individualized and predictive medicine to develop novel care pathways by a multi-disciplinary group centred around the patients. Stakeholders: Include patients, health care professionals (pharmacists and physicians), authorities, patient's associations, private and public sectors. Results: MASK is deployed in 23 countries and 17 languages. 26,000 users have registered. EU grants (2018): MASK is participating in EU projects (POLLAR: impact of air POLLution in Asthma and Rhinitis, EIT Health, DigitalHealthEurope, Euriphi and Vigour). Lessons learnt: (i) Adherence to treatment is the major problem of allergic disease, (ii) Self-management strategies should be considerably expanded (behavioural), (iii) Change management is essential in allergic diseases, (iv) Education strategies should be reconsidered using a patient-centred approach and (v) Lessons learnt for allergic diseases can be expanded to chronic diseases. © 2019 The Author(s).

mHealth, such as apps running on consumer smart devices is becoming increasingly popular and has the potential to profoundly affect healthcare and health outcomes. However, it may be disruptive and results achieved are not always reaching the goals. Allergic Rhinitis and its Impact on Asthma (ARIA) has evolved from a guideline using the best evidence-based approach to care pathways suited to real-life using mobile technology in allergic rhinitis (AR) and asthma multimorbidity. Patients largely use over-the-counter medications dispensed in pharmacies. Shared decision making centered around the patient and based on self-management should be the norm. Mobile Airways Sentinel networK (MASK), the Phase 3 ARIA initiative, is based on the freely available MASK app (the Allergy Diary, Android and iOS platforms). MASK is available in 16 languages and deployed in 23 countries. The present paper provides an overview of the methods used in MASK and the key results obtained to date. These include a novel phenotypic characterization of the patients, confirmation of the impact of allergic rhinitis on work productivity and treatment patterns in real life. Most patients appear to self-medicate, are often non-adherent and do not follow guidelines. Moreover, the Allergy Diary is able to distinguish between AR medications. The potential usefulness of MASK will be further explored by POLLAR (Impact of Air Pollution on Asthma and Rhinitis), a new Horizon 2020 project using the Allergy Diary. © 2018 The Author(s).

Background: Hyperreflective foci have been described in OCT imaging of patients with retinal vascular diseases. It has been suggested that they may play a role as a prognostic factor of visual outcomes in these diseases. The purpose of this study is to describe the presence of hyperreflective foci in patients with non-infectious uveitic macular edema and evaluate their behavior after treatment. Methods: We conducted a multicenter, prospective, observational, 12-month follow-up study. Inclusion criteria were age > 18 years and a diagnosis of non-infectious uveitic macular edema, defined as central macular thickness of > 300 mu m as measured by OCT and fluid in the macula. Collected data included best corrected visual acuity, central macular thickness and the presence, number and distribution (inner or outer retinal layers) of hyperreflective foci. Evaluations were performed at baseline, and at 1, 3, 6, and 12 months after starting treatment. Results: We included 24 eyes of 24 patients. The frequency of patients with >= 11 hyperreflective foci was 58.4% at baseline, falling to 20.8% at 12 months. Further, hyperreflective foci were observed in the outer retinal layers in 50% of patients at baseline and just 28.6% at 12 months. Mean LogMAR visual acuity improved from 0.55 (95% CI 0.4-0. 71) at baseline to 0.22 (95% CI 0.08-0.35) at 12 months (p < 0.001). Mean central macular thickness decreased from 453.83 mu m (95% CI 396.6-511) at baseline to 269.32 mu m (95% CI 227.7-310.9) at 12 months (P < 0.001). Central macular thickness was associated with number (p = 0.017) and distribution (p = 0.004) of hyperreflective foci. Conclusions: We have observed hyperreflective foci in most of our patients with non-infectious uveitic macular edema. During follow-up and after treatment, the number of foci diminished and they tended to be located in the inner layers of the retina. This work was supported by grants from: Spanish Ministry of Economy, Industry and Competitivity, Carlos III Health Institute: PI 13/02148, cofinanced by the European Regional Development Fund.

Geographic atrophy is characterized by severe visual deficit whose etiology and pathophysiology are yet to be elucidated. As a working hypothesis, oxidative damage could trigger a chronic inflammation in Bruch's membrane-RPE-choriocapillaris complex, mostly due to complement pathway overactivation. Some individuals with mutations in the complement system and other factors have diminished capacity in the modulation of the inflammatory response, which results in cell damage and waste accumulation. This accumulation of intracellular and extracellular waste products manifests as drusen and pigmentary changes that precede the atrophy of photoreceptors, RPE, choriocapillaris with an ischemic process with decreased choroid flow. All these processes can be detected as tomographic findings and autofluorescence signals that are useful in the evaluation of patients with atrophic AMD, which helps to establish an individualized prognosis. Anti-inflammatory, antioxidant and therapies that decrease the accumulation of toxins for the preservation of the RPE cells and photoreceptors are being investigated in order to slow down the progression of this disease.

Membrane technologies have seen a significant growth and increase in application in the last two decades. Membrane systems are now available in several different forms and sizes, each uniquely fitting a particular need and application. With the growing confidence to tailor–make membranes with desired characteristics, the applications can be extended to the separation / decontamination of a number of aqueous streams in chemical engineering or in the nuclear fuel cycle. The chemical and engineering communities are already paying significant attention to the quest for technologies that would lead us to the goal of technological sustainability. Amongst the various separation techniques, membrane based separation methods are getting increasingly popular due to factors such as high efficiency, and low in power consumption and easy scale–up due to a compact design etc. Also, in a modern approach, membrane contactors have proved to be an efficient contacting device, due to their high area per unit volume that results in high mass transfer rates. They are not only compact but also eliminate several of the problems faced in conventional processes such as ion exchange, solvent extraction, and precipitation.

It has been hypothesized that at sufficiently high levels of oceanic salinity turbulence it should be possible to observe acoustic backscattering. However, there have been limited in situ measurements to confirm this hypothesis. Using an autonomous underwater vehicle equipped with upward and downward looking 1.2 MHz acoustic Doppler current profilers and with turbulence and fine scale sensors, measurements were performed in a region of intense turbulence and a strong salinity gradient. The approach taken was to correlate variations in the backscattered acoustic intensity, I, with a theoretical acoustic backscattering cross section per volume for salinity turbulence, σ(s), to obtain an estimated scattering cross section per volume, σ(e). Results indicated that of order 50% of the observed region was characterized by salinity turbulence induced backscattering.

INTRODUÇÃO: A inclusão de intervenções focadas na família, através da terapia unifamiliar, ou da terapia multifamiliar (TGMF) vem crescendo como uma forma de enfrentar um problema tão grave e complexo como é a dependência química. OBJETIVOS: Investigar e avaliar fatores associados à adesão ao tratamento multifamiliar no tratamento de dependentes químicos hospitalizados. MÉTODO: A pesquisa é um estudo transversal retrospectivo, com uma amostra de 672 famílias participantes da TGMF durante o período de seis anos (de março 1997 a julho de 2003). Foi realizado um estudo dos fatores sociodemográficos como idade, sexo, tempo de uso da substância e quanto ao tipo de droga mais prevalente e investigada a associação entre o grau de parentesco do familiar participante do programa e a adesão ao tratamento multifamiliar. Foram pesquisados 672 prontuários de sujeitos que estiveram internados e ingressaram no programa de tratamento multifamiliar e os relatos das sessões descritos pelo terapeuta coordenador do grupo. RESULTADOS: Há associação entre a participação da família e adesão ao tratamento. A participação de dois ou mais familiares repercute na adesão. DISCUSSÃO: Os resultados sugerem que inclusão de um número maior de familiares poderá repercutir em uma maior adesão ao tratamento.

Lormetazepam (1 mg) and diazepam (5 mg) were compared in a double-blind study of 100 patients with sleep disorders associated with a medical illness. Assignment to one of two treatment groups was at random. Lormetazepam had a greater hypnotic effect than diazepam in all significant variables (P less than 0.05). There was no hangover effect or other side effects with lormetazepam, which was thus superior to diazepam also in this respect (P less than 0.05).

The selection of pharmacotherapy for patients with allergic rhinitis (AR) depends on several factors, including age, prominent symptoms, symptom severity, control of AR, patient preferences, and cost. Allergen exposure and the resulting symptoms vary, and treatment adjustment is required. Clinical decision support systems (CDSSs) might be beneficial for the assessment of disease control. CDSSs should be based on the best evidence and algorithms to aid patients and health care professionals to jointly determine treatment and its step-up or step-down strategy depending on AR control. Contre les MAladies Chroniques pour un VIeillissement Actif en Languedoc-Roussillon (MACVIA-LR [fighting chronic diseases for active and healthy ageing]), one of the reference sites of the European Innovation Partnership on Active and Healthy Ageing, has initiated an allergy sentinel network (the MACVIA-ARIA Sentinel Network). A CDSS is currently being developed to optimize AR control. An algorithm developed by consensus is presented in this article. This algorithm should be confirmed by appropriate trials. © 2016 The Authors

The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma and rhinitis and (3) to develop guidelines with all stakeholders that could be used globally for all countries and populations. ARIA - disseminated and implemented in over 70 countries globally - is now focusing on the implementation of emerging technologies for individualized and predictive medicine. MASK [MACVIA (Contre les Maladies Chroniques pour un Vieillissement Actif)-ARIA Sentinel NetworK] uses mobile technology to develop care pathways for the management of rhinitis and asthma by a multi-disciplinary group and by patients themselves. An app (Android and iOS) is available in 20 countries and 15 languages. It uses a visual analogue scale to assess symptom control and work productivity as well as a clinical decision support system. It is associated with an inter-operable tablet for physicians and other health care professionals. The scaling up strategy uses the recommendations of the European Innovation Partnership on Active and Healthy Ageing. The aim of the novel ARIA approach is to provide an active and healthy life to rhinitis sufferers, whatever their age, sex or socio-economic status, in order to reduce health and social inequalities incurred by the disease. © 2016 The Author(s).

The availability of allergen molecules (‘components’) from several protein families has advanced our understanding of immunoglobulin E (IgE)-mediated responses and enabled ‘component-resolved diagnosis’ (CRD). The European Academy of Allergy and Clinical Immunology (EAACI) Molecular Allergology User's Guide (MAUG) provides comprehensive information on important allergens and describes the diagnostic options using CRD. Part A of the EAACI MAUG introduces allergen molecules, families, composition of extracts, databases, and diagnostic IgE, skin, and basophil tests. Singleplex and multiplex IgE assays with components improve both sensitivity for low-abundance allergens and analytical specificity; IgE to individual allergens can yield information on clinical risks and distinguish cross-reactivity from true primary sensitization. Part B discusses the clinical and molecular aspects of IgE-mediated allergies to foods (including nuts, seeds, legumes, fruits, vegetables, cereal grains, milk, egg, meat, fish, and shellfish), inhalants (pollen, mold spores, mites, and animal dander), and Hymenoptera venom. Diagnostic algorithms and short case histories provide useful information for the clinical workup of allergic individuals targeted for CRD. Part C covers protein families containing ubiquitous, highly cross-reactive panallergens from plant (lipid transfer proteins, polcalcins, PR-10, profilins) and animal sources (lipocalins, parvalbumins, serum albumins, tropomyosins) and explains their diagnostic and clinical utility. Part D lists 100 important allergen molecules. In conclusion, IgE-mediated reactions and allergic diseases, including allergic rhinoconjunctivitis, asthma, food reactions, and insect sting reactions, are discussed from a novel molecular perspective. The EAACI MAUG documents the rapid progression of molecular allergology from basic research to its integration into clinical practice, a quantum leap in the management of allergic patients. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd

Radial growth rate, intracellular laccases and proteases activities, and protein content were evaluated in five strains of Pleurotus ostreatus, grown on starch-based and glucose-based agar media containing different concentrations of the glucose analogue 2-deoxyglucose (2-DG). Productivity of the strains in pilot scale cultivation was also determined. The mycelium of four strains had approximately between 0.6- to 3-fold higher protein content when grown on glucose medium containing 0.01 g/L of 2-DG than when grown on glucose medium. The radial growth rate and intracellular laccases activity of some strains showed a positive and a negative correlation with the productivity, respectively. These results suggest that the strains with high radial growth rate and low intracellular laccases activity on glucose without 2-DG, on starch without 2-DG or on glucose containing 0.01 g/L of 2-DG are highly productive in pilot production farm.Avaliou-se o crescimento radial, as atividades de proteases e lacases e o conteúdo protéico de cinco cepas de Pleurotus ostreatus cultivado em agar à base de amido e à base de glicose contendo diferentes concentrações de 2-deoxiglicose (2-DG), um análogo da glicose. A produtividade das cepas em cultivo em escala piloto foi também determinada. Em quatro cepas o conteúdo protéico do micélio foi aproximadamente 0,6 a 3 vezes maior quando foram cultivadas em meio à base de glicose contendo 0,01g/L de 2-DG. O crescimento radial e a atividade de lacases apresentaram correlação positiva e negativa, respectivamente, com a produtividade. Esses resultados sugerem que as cepas com elevada taxa de crescimento radial e baixa atividade de lacases em glicose sem 2-DG, ou em amido sem 2-DG, ou em glicose com 0,01 g/L de 2-DG, são altamente produtivas em cultivo em escala piloto.

Background: Motor fluctuations and dyskinesias affect many parkinsonian patients chronically treated with levodopa. Imbalance between gabaergic direct and indirect striatopallidal pathways may originate them. ManipulatingGABA neurotransmission may be effective in the treatment of these patients. Gabapentin is an antiepileptic drug that increases the synthesis and release of GABA. Previous studies suggest that gabapentin may be useful in Parkinson disease (PD). Objective: To know the effects of gabapentin on the motor response to levodopa in PD patients with motor complications. Design: A randomized double-blind, placebo-controlled, cross-over trial with four weeks of treatment. Setting: A tertiary referral center. Participants: Twenty subjects with PD and motor fluctuations and dyskinesias on stable antiparkinsonian treatment, took gabapentin up to a maximum dose of 2.400 mg/d in three doses and placebo. Methods: Three levodopa challenges were performed: at the beginning of the study and at the end of each period of treatment (4 weeks). Basal (off) and best (on) motor status were assessed by the UPDRS III. Latency to peak effect, magnitude of motor response (difference between "on" and "off" scores in the UPDRS III), duration of motor response and severity and duration of dyskinesias after each levodopa challenge were assessed. Patients' diaries were administered. Results: Fifteen patients completed the study. A significant improvement in the basal UPDRS III resulting in a significant reduction in the magnitude of the motor response after gabapentin was obtained (P < 0.001). No other changes were observed, either on pharmacological parameters or in levodopa-induced dyskinesias. Number of daily hours spent in "on," "on with dyskinesias" and "off" also remained unchanged. Tolerance was good, dizziness being the most common side effect. Conclusion: Gabapentin improved parkinsonian symptoms (basal UPDRS III and magnitude of the motor response) following levodopa. This improvement was not reflected in the daily motor situation of patients. Dyskinesias remained unchanged. Gabapentin was well tolerated. Further studies are needed to know the impact of these results in the long-term.

The extraction of zinc(II) from spent pickling hydrochloric acid solutions obtained in zinc hot-dip galvanizing plants was studied. Tributyl phosphate and its mixtures with di(2-ethylhexyl)phosphoric acid (DEHPA), HOE F 2562, ALIQUAT 336, ALAMINE 304, ALAMINE 308, ALAMINE 310, ALAMINE 336, and CYANEX 301 were used as extractants. The acidic extractants (CYANEX 301 and DEHPA) did not extract both zinc(II) and iron(III) from 10% HCl. Precipitation occurred or stable emulsions were formed when ALAMINE 304, ALAMINE 308, and ALAMINE 310 were used. Each of the other reagents coextracted both zinc(II) and iron(III). The latter had to be reduced to iron(II) prior to extraction. Tributyl phosphate and HOE F 2562 showed the best extraction performance. ALAMINE 336 and ALIQUAT 336 induced the oxidation of iron(II) to iron(III), thus enhancing the coextraction of iron. Zinc(II) could be effectively stripped from the loaded phases containing TBP and HOE F 2562 with water. A higher efficiency of stripping was observed ...

Resumen El contenido de este trabajo se enmarca en un estudio mas amplio, en fase de redaccion, cuyo objetivo fundamental pretende detectar y analizar aquellas estrategias que utiliza el maestro ordinario en el aula, a la hora de establecer relaciones comunicativas con sus alumnos con dificultades del lenguaje. Fruto del trabajo se diseno un sistema de categorias resultado de un proceso de reelaboracion de otras en funcion de diferentes criterios selectivos. Este sistema categorial pretende ser util a la hora de analizar las interacciones en el aula entre el docente y los alumnos con dificultades del lenguaje en ambitos de investigacion, con el fin de contribuir a la difusion de herramientas que faciliten y mejoren el sistema de analisis de las interacciones comunicativas en contextos escolares naturales.