442 research outputs found

    Boron concentration profiling by high angle annular dark field-scanning transmission electron microscopy in homoepitaxial delta-doped diamond layers

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    To develop further diamond related devices, the concentration and spatial location of dopants should be controlled down to the nanometer scale. Scanning transmission electron microscopy using the high angle annular dark field mode is shown to be sensitive to boron doping in diamond epilayers. An analytical procedure is described, whereby local boron concentrations above 1020 cm-3 were quantitatively derived down to nanometer resolution from the signal dependence on thickness and boron content. Experimental boron local doping profiles measured on diamond p-/p++/p- multilayers are compared to macroscopic profiles obtained by secondary ion mass spectrometry, avoiding reported artefacts.4 page

    (R)-(1-Ammonio­prop­yl)phospho­nate

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    The title compound, C3H10NO3P, crystallizes in its zwitterionic form, H3N+CH(C2H5)PO(O−)(OH), with the asymmetric unit being composed by two of such entities (Zâ€Č = 2). The crystal packing leads to a sequence of hydro­phobic and hydro­philic layers. While the hydro­phobic layer comprises the aliphatic substituent groups, the hydro­philic one is held together by a series of strong and rather directional N+—H⋯O and O—H⋯O hydrogen bonds

    Desmontando la seguridad en las polĂ­ticas de empleo: la propuesta europea de flexiguridad

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    Although it is not very old, the concept of flexicurity has a long history due to the substantive weight it has been given in all European employment policies under the auspices of the European Social Model. This is a con-cept that is developed in a context of lax political regula-tion (soft governance) and where there is no tradition of specific social and employment policies, as it is an in-ternational institutional space where different traditions of the Member States could converge. Taking these as-pects into account, this article aims to delve deeper into the ideological-political meaning and character of the concept of flexicurity. To this end, firstly, we investigate its production context and the theories and regulatory paradigms on which it is based, secondly, an analysis of the discourse of some of the European Commission’s texts focusing on this concept is carried out, highlight-ing the unequal semantic load of flexibility and security within it and the semantic transformation that “security” undergoes. This evidence reveals a new reality in the world of work, in which workers and employers seem to have exchanged roles: workers have a moral duty to empower themselves with adaptive skills (their employ-ment situation will depend on whether or not they have done so) while employers become vulnerable to new economic flows.A pesar de no tener muchos años de vida, el concepto de flexiguridad cuenta con una dilatada historia debido al peso sustantivo que se le ha concedido en todas las polĂ­ticas de empleo europeas auspiciadas por el Modelo Social Europeo. Se trata de un concepto que se gesta en un contexto de regulaciĂłn polĂ­tica laxa (soft governance) en el que no existe una tradiciĂłn de polĂ­ticas sociales y de empleo especĂ­fica, al ser un espacio institucional internacional donde podrĂ­an confluir diversas tradiciones de los Estados miembros. Teniendo en cuenta estos aspectos, este artĂ­culo se propone profundizar en el significado y carĂĄcter ideolĂłgico-polĂ­tico del concepto de flexiguridad. Para ello, en primer lugar, indagamos en su contexto de producciĂłn y en las teorĂ­as y paradigmas de regulaciĂłn en los que se basa; en segundo lugar, se realiza un anĂĄlisis del discurso de algunos de los textos de la ComisiĂłn Europea centrados en este concepto, evidenciando la carga semĂĄntica desigual de flexibilidad y seguridad en su seno y la transformaciĂłn semĂĄntica que la seguridad experimenta. Esta evidencia descubre una nueva realidad del mundo del trabajo en la que trabajador y empresario parecen haber intercambiado sus roles: el trabajador tiene el deber moral de empoderarse mediante la adquisiciĂłn de capacidades adaptativas (su situaciĂłn laboral dependerĂĄ de haberlo hecho o no), mientras que el empresario deviene en un agente vulnerable ante los nuevos flujos econĂłmicos

    Glycine methyl ester hydro­chloride

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    The title compound [systematic name: (methoxy­carbonyl­meth­yl)ammonium chloride], crystallizes as a salt, C3H8NO2 +·Cl−, with the charged species inter­acting mutually via strong and highly directional N+—H⋯Cl− hydrogen bonds which lead to the formation of a supra­molecular tape running parallel to the c axis. Tapes close pack in the solid state mediated by multipoint recognition synthons based on weak C—H⋯O inter­actions and van der Waals contacts between adjacent methyl groups

    Electrocatalytic performance and stability of nanostructured Fe–Ni pyrite-type diphosphide catalyst supported on carbon paper

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    A simple and effective method to prepare an active and stable nanostructured working electrode for electrochemical water splitting is described. Specifically, mixed Fe–Ni diphosphide was prepared by sputtering a 200-nm-thick layer of Permalloy onto carbon paper gas diffusion layer followed by gas transport phosphorization reaction. The mass density of the resultant diphosphide phase was established to be 1.1 mg/cm2. Energy-dispersive X-ray microanalysis shows that the actual elemental composition of the resultant ternary electrocatalyst is approximately Fe0.2Ni0.8P2, while the powder X-ray diffraction analysis confirms that the electrocatalyst crystallizes in NiP2 cubic pyrite-like structure. As a cathode for hydrogen evolution reaction (HER) in acidic and alkaline electrolytes, this earth-abundant electrode has exchange current densities of 6.84103 and 3.16103 mA/cm2 and Tafel slopes of 55.3 and 72.2 mV/dec, respectively. As an anode for oxygen evolution reaction (OER) in alkaline electrolyte, the electrode shows an exchange current density of 2.88104 mA/cm2 and Tafel slope of 49.3 mV/dec. The observed high activity of the electrode correlates well with its electronic structure, which was assessed by density functional theory (DFT) calculations. The stability of Fe0.2Ni0.8P2 electrocatalyst in HER and OER was evaluated by means of accelerated degradation test and chronopotentiometry. The results of these experiments elucidate partial dissolution and entire chemical transformation of Fe0.2Ni0.8P2 as the main mechanisms of the electrode degradation during HER and OER, respectively. Overall, our findings could facilitate the composition-based design of active, stable, and durable phosphide electrodes for electrochemical water splitting.We thank all members of the Nanomaterials Synthesis Unit at the INL for their fruitful scientific and technical input, as well as Dr. X. Wang for his help with the electrocatalytic data analysis. This investigation has benefited from the financial support provided by the European Union Horizon 2020 NMP programme through the CritCat project under grant agreement no. 686053, as well as ERDF funds through the Portuguese Operational Programme for Competitiveness and Internationalization (COMPETE 2020), and National Funds through the Portuguese Foundation for Science and Technology (FCT), under the PrintPV project PTDC/CTM-ENE/5387/2014 (grant agreement no. 016663). J.D.C. thanks the FCT PhD grant SFRH/BD/79393/2011, while J.L.L. thanks Marie-Curie-ITN607904-SPINOGRAPH project for the PhD grant

    Modeling photosynthetically active radiation from satellite-derived estimations over mainland Spain

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    A model based on the known high correlation between photosynthetically active radiation (PAR) and global horizontal irradiance (GHI) was implemented to estimate PAR from GHI measurements in this present study. The model has been developed using satellite-derived GHI and PAR estimations. Both variables can be estimated using Kato bands, provided by Satellite Application Facility on Climate Monitoring (CM-SAF), and its ratio may be used as the variable of interest in order to obtain the model. The study area, which was located in mainland Spain, has been split by cluster analysis into regions with similar behavior, according to this ratio. In each of these regions, a regression model estimating PAR from GHI has been developed. According to the analysis, two regions are distinguished in the study area. These regions belong to the two climates dominating the territory: an Oceanic climate on the northern edge; and a Mediterranean climate with hot summer in the rest of the study area. The models obtained for each region have been checked against the ground measurements, providing correlograms with determination coefficients higher than 0.99This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO) [Project CGL2016-79284-P AEI/FEDER/UE]S

    The social wellbeing of irrigation water. A demand-side integrated valuation in a Mediterranean agroecosystem

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    [EN] Irrigation water is a vital input for agricultural production. The supply of irrigation water to crops enhances land productivity and affects the agroecosystem functioning. Agroecosystems co-provide a wide range of agroecosystem services and disservices, which contribute positively and negatively, respectively, to human wellbeing. Therefore, irrigated agroecosystems produce several positive and negative outcomes in relation to society, and agricultural water management is key to the provision of adequate incentives for the enhancement of social wellbeing. In such a context, the aim of this work was to value the contribution of water to the provision of agroecosystem services and disservices, as a way to summarise the contribution of irrigation to social wellbeing. To this end, a demand-side integrated valuation of agroecosystem services and disservices was carried out for both rain-fed and irrigated agriculture in two different agroecosystems of the Region of Murcia (south-eastern Spain), a semi-arid western Mediterranean region characterised by water scarcity. In addition, the intensity of the agricultural water use was considered by distinguishing traditional and highly-intensive irrigated agroecosystems. Almond and lemon, two woody crops, were employed to develop the economic valuation in rain-fed and irrigated agroecosystems, respectively. The assessment of biophysical indicators to quantify the provision of services and disservices and their economic valuation, using market and non-market methods, were used. The results show that the contribution of water to social wellbeing is valued at 9000-12,300 euro/ha/year, being greater when the intensive use of agricultural water is promoted. The net economic value of all categories of agroecosystem services and disservices increases when irrigation water is supplied. Notwithstanding, the greatest contribution is due to the increase in provisioning services, mainly food provision in the case of the highly-intensive agroecosystem. Traditional irrigated agroecosystems make a greater contribution to regulating and cultural agroecosystem services. Hence, agricultural water management should focus on increasing the contribution of irrigated agroecosystems to human wellbeing.This work was supported by the AgriCambio project (Grant PID2020- 114576RB-I00 funded by MCIN/AEI/ 10.13039/501100011033). JosÂże A. Zabala, VĂ­ctor MartĂ­nez-GarcĂ­a and JosÂże A. Albaladejo-GarcĂ­a acknowledge the financial support from the Spanish Ministry of Education and Personal Training (FPU 16/03473; FPU19/05143; FPU 16/ 03562)Alcon, F.; Zabala, J.; MatĂ­nez-GarcĂ­a, V.; Albaladejo, J.; LĂłpez-Becerra, E.; De Miguel, MD.; MartĂ­nez-Paz, JM. (2022). The social wellbeing of irrigation water. A demand-side integrated valuation in a Mediterranean agroecosystem. Agricultural Water Management. 262. https://doi.org/10.1016/j.agwat.2021.10740026

    Histopathological characteristics of cutaneous lesions caused by Leishmania Viannia panamensis in Panama

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    Cutaneous leishmaniasis (CL) is an endemic disease in the Republic of Panama, caused by Leishmania (Viannia) parasites, whose most common clinical manifestation is the presence of ulcerated lesions on the skin. These lesions usually present a chronic inflammatory reaction, sometimes granulomatous, with the presence of lymphocytes, plasma cells and macrophages. This study describes the histopathological characteristics found in the skin lesions of patients with CL caused by Leishmania (V.) panamensis in Panama. We analyzed 49 skin biopsy samples from patients with clinical suspicion of CL, by molecular tests (PCR for subgenus Viannia and HSP-70) and by Hematoxylin-Eosin staining. Samples were characterized at the species level by PCR-HSP-70/RFLP. From the 49 samples studied, 46 (94%) were positive by PCR and were characterized as Leishmania (V.) panamensis. Of these, 48% were positive by Hematoxylin-Eosin staining with alterations being observed both, in the epidermis (85%) and in the dermis (100%) of skin biopsies. The inflammatory infiltrate was characterized according to histopathological patterns: lymphohistiocytic (50%), lymphoplasmacytic (61%) and granulomatous (46%) infiltration, being the combination of these patterns frequently found. The predominant histopathological characteristics observed in CL lesions caused by L. (V.) panamensis in Panama were: an intense inflammatory reaction in the dermis with a combination of lymphohistiocytic, lymphoplasmacytic and granulomatous presentation patterns and the presence of ulcers, acanthosis, exocytosis and spongiosis in the epidermis

    Signs of Overload After an Intensified Training

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    [EN] This study investigated eff ects of a 9-week intensified aerobic training and 3-weeks of recovery on signs of overload in 9 healthy active young males. Blood and saliva samples were collected and psychological questionnaires were administered during baseline (T1), intermediate load (T2), maximal load (T3), and recovery (T4) periods. Maximal oxygen uptake increased and blood lactate concentration decreased in T3, while running time in a 3 000 m track fi eld test was significantly shorter. No signifi cant changes were found in hematocrit, haemoglobin concentration, white blood cell count, lactate dehydrogenase, transaminases, interleukin-6, tumour necrosis factor- α , myeloperoxidase and markers of oxidative stress in plasma, or salivary cortisol and testosterone. Increases in diff erent negative aff ectscales and in the total mood disturbance score of the Profi le of Mood States were observed during T3. Scores in the stress scales of the Recovery- Stress Questionnaire for Athletes and in the State Anxiety Scale of the State-Trait Anxiety Inventory also showed signifi cant increases during T3. The lack of eff ects in biomarkers together with the changes observed in psychological assessment indicates that an intensifi ed training can produce psychological disturbances prone to early overreaching development. Additionally, it seems that psychological parameters are sensitive markers to detect stress produced by load increases.SIThis work was supported by the Acción Estratégica Sobre el Deporte, Spain (grants n ° 2006-56141-C03-01 to J. G., n ° 2006- 56141-C03-02 to S.M., and n ° 2006-56141-C03-03 to F.S.
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