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Considering any graph technical inefficiency measure, we show that the so-called standard or traditional approach for decomposing profit inefficiency relying on Fenchel-Mahler inequalities obtained from duality theory, establishes that profit inefficiency is greater than or equal to the product of technical inefficiency times a positive factor expressed in monetary units. This product is identified as the technical profit inefficiency and its difference with respect to the profit inefficiency as the allocative profit inefficiency. Dividing profit inefficiency by the mentioned positive factor one obtains the normalized (units’ invariant) profit inefficiency of the firm, which is a pure number, and can be decomposed into the sum of technical inefficiency and the normalized allocative profit inefficiency, usually called allocative inefficiency. We propose a new decomposition based on equalities that starts from the input and output slacks connecting the firm with the frontier benchmark, obtained through the pre-specified technical inefficiency measure. Profit inefficiency is then decomposed into the value of the technological gap and the profit inefficiency of the frontier benchmark. Expressing the value of the technological gap as the product of the technical inefficiency times a certain normalizing factor, we deduce a new normalized profit inefficiency decomposition. Our decomposition ensures that the allocative efficiency of a firm corresponds to that of its benchmark on the frontier and therefore avoids the possibility of overestimating it. We compare the traditional and the general direct approach and show that the new decomposition is conceptually sound and more accurate, with the only exception of the family of directional distance functions, for which both decompositions are equivalent.

© 2016 IOP Publishing Ltd. The authors would like to acknowledge the C A I de Técnicas Físicas of the Universidad Complutense de Madrid for the ion implantations and metallic evaporations, the Nanotechnology and Surface Analysis Services of the Universidad de Vigo C.A.C.T.I. for ToF-SIMS measurements and Dr J P González García from CIEMAT for reflectance measurements. Research by E García-Hemme was supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM). J Olea acknowledges financial support from the MICINN within the program Juan de la Cierva (JCI-2011-10402), under which this research was undertaken. D Pastor acknowledges the financial support to the grant EX-2010-0662 from the Spanish Science Ministry. This work was partially supported by the Spanish MINECO (Economic and Competitiviness Ministery) through grant TEC 2013-41730-R. The authors acknowledge the financial support from la Comunidad de Madrid throughout the funding of the project, MADRID-PV (S2013/MAE-2780)., Silicon samples were implanted with high Ti doses and subsequently processed with the pulsed-laser melting technique. The electronic transport properties in the 15–300 K range and the room temperature spectral photoresponse at energies over the bandgap were measured. Samples with Ti concentration below the insulator-metal (I-M) transition limit showed a progressive reduction of the carrier lifetime in the implanted layer as Ti dose is increased. However, when the Ti concentration exceeded this limit, an extraordinary recovery of the photoresponse was measured. This result supports the theory of intermediate band materials and is of utmost relevance for photovoltaic cells and Si-based detectors., Ministerio de Economía y Competitividad (MINECO), Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Campus de Excelencia Internacional Moncloa UCM-UPM, PICATA Programa Internacional de Captación de Talento Convocatorias Campus Moncloa, Ayudas para contratos Juan de la Cierva (MICINN), Ministerio de Ciencia y Tecnología (MCYT), España, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© American Institute of Physics. This work has been supported by the Spanish Ministry of Science and Technology under Contract Nos. MAT2004-0664 and MAT2004-02875. The authors wish to thank Dr. M. Marsal for her expert assistance with the EDX measurements., We have studied the effects of rapid thermal annealing at 1300 degrees C on GaN epilayers grown on AlN buffered Si(111) and on sapphire substrates. After annealing, the epilayers grown on Si display visible alterations with craterlike morphology scattered over the surface. The annealed GaN/Si layers were characterized by a range of experimental techniques: scanning electron microscopy, optical confocal imaging, energy dispersive x-ray microanalysis, Raman scattering, and cathodoluminescence. A substantial Si migration to the GaN epilayer was observed in the crater regions, where decomposition of GaN and formation of Si3N4 crystallites as well as metallic Ga droplets and Si nanocrystals have occurred. The average diameter of the Si nanocrystals was estimated from Raman scattering to be around 3 nm. Such annealing effects, which are not observed in GaN grown on sapphire, are a significant issue for applications of GaN grown on Si(111) substrates when subsequent high-temperature processing is required., Spanish Ministry of Science and Technology, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2023 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., In this article, we study the effect of the inversion charge ( Q inv ) in a solar cell based on the hole-selective characteristic of substoichiometric molybdenum oxide (MoO x ) and vanadium oxide (VO x ) deposited directly on n-type silicon. We measure the capacitance–voltage ( C – V ) curves of the solar cells at different frequencies and explain the results taking into account the variation of the space charge and the existence of Q inv in the c-Si inverted region. The high-frequency capacitance measurements follow the Schottky metal–semiconductor theory, pointing to a low inversion charge influence in these measurements. However, for frequencies lower than 20 kHz, an increase in the capacitance is observed, which we relate to the contribution of the inversion charge. In addition, applying the metal–semiconductor theory to the high-frequency measurements, we have obtained the built-in voltage potential and show new evidence about the nature of the conduction process in this structure. This article provides a better understanding of the transition metal oxide/n-type crystalline silicon heterocontact., The authors would like to acknowledge the CAI de Técnicas Físicas of the Universidad Complutense de Madrid. The authors would also like to thank the Mexican grants program CONACyT for its financial collaboration., Peer Reviewed, Postprint (author's final draft)

We present a detailed investigation on the formation of supersaturated GaAs using Ti+ implantation followed by nanosecond Pulsed Laser Melting (PLM). We have synthesized high-crystal quality supersaturated GaAs layers with concentrations of Ti above the insulator to metal transition (Mott limit). The Ti-implanted concentration depth profiles after PLM obtained by Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) show a redistribution of Ti impurities within the first hundred nanometers and superficial concentration up to 1 × 1021 cm−3. Raman spectroscopy of these Ti supersaturated, and regrown GaAs samples shows a sharp crystalline peak and tensile strain due to the Ti lattice incorporation. Scanning Transmission Electron Microscopy (STEM) and high-resolution Transmission Electron Microscopy (TEM) images show a good GaAs crystallinity after the PLM process. Energy-Dispersive X-ray Spectroscopy (EDS) reveals an enhanced Ti signal inside bubble-like structures and an appearance of interface oxide layer with all processed samples.

© 2022 IOP Publishing Ltd. Authors wish to acknowledge assistance from CAI de Técnicas Físicas (Unidad de Implantación Iónica) and CAI de Técnicas Químicas (Espectroscopía Raman y Correlación) from the Universidad Complutense de Madrid with the Ion Implantations and Raman measurements, respectively. We also acknowledge Servicio de Nanotecnología y Análisis de Superficies del CACTI de la Universidad de Vigo for ToF-SIMS measurements and ICTS-CNM from Madrid for the SEM images. This work was partially supported by the Projects MADRID-PV2 (P2018/EMT-4308) funded by the Comunidad Autónoma de Madrid with the support from FEDER Funds and Projects SCCell (PID2020-116508RB-I00), HyperPHIR (PID2020-117498RB-I00) and SCALED (PID2019-109215RB-C42), funded by the Spanish Ministry of Science and Innovation. D Caudevilla would also acknowledge the Grant PRE2018-083798, financed by MICINN and European Social Fund. F Pérez-Zenteno would also like to acknowledge Grant 786327 form Mexican grants program CONACyT., In this work we have successfully hyperdoped germanium with tellurium with a concentration peak of 10(21) cm(-3). The resulting hyperdoped layers show good crystallinity and sub-bandgap absorption at room temperature which makes the material a good candidate for a new era of complementary metal-oxide-semiconductor-compatible short-wavelength-infrared photodetectors. We obtained absorption coefficients ci higher than 4.1 x 10(3) cm(-1) at least up to 3 mu m. In this study we report the temperature-dependency electrical properties of the hyperdoped layer measured in van der Pauw configuration. The electrical behaviour of this hyperdoped material can be explained with an electrical bilayer coupling/decoupling model and the values for the isolated hyperdoped layer are a resistivity of 4.25 x 10(-3) Omega.cm with an electron-mobility around -100 cm(2) V-1 s(-1)., Ministerio de Ciencia e innovación (MICINN)., Ministerio de Ciencia e Innovación (MICINN)/FEDER, Comunidad de Madrid/ FEDER, Mexican grants program CONACyT, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

According to intermediate band (IB) theory, it is possible to increase the efficiency of a solar cell by boosting its ability to absorb low-energy photons. In this study, we used a hyperdoped semiconductor approach for this theory to create a proof of concept of different silicon-based IB solar cells. Preliminary results show an increase in the external quantum efficiency (EQE) in the silicon sub-bandgap region. This result points to sub-bandgap absorption in silicon having not only a direct application in solar cells but also in other areas such as infrared photodetectors. To establish the transport mechanisms in the hyperdoped semiconductors within a solar cell, we measured the J–V characteristic at different temperatures. We carried out the measurements in both dark and illuminated conditions. To explain the behavior of the measurements, we proposed a new model with three elements for the IB solar cell. This model is similar to the classic two-diodes solar cell model but it is necessary to include a new limiting current element in series with one of the diodes. The proposed model is also compatible with an impurity band formation within silicon bandgap. At high temperatures, the distance between the IB and the n-type amorphous silicon conduction band is close enough and both bands are contacted. As the temperature decreases, the distance between the bands increases and therefore this process becomes more limiting., The authors would like to thank the Physical Sciences Research Assistance Centre (CAI de Técnicas Físicas) of the Complutense University of Madrid. This study was partially funded by Project MADRID-PV2 (P2018/EMT-4308), with aid from the Regional Government of Madrid and the ERDF, by the Spanish Ministry of Science and Innovation/National Research Agency (MCIN/AEI) under grants TEC2017- 84378-R, PID2019-109215RB-C41, PID2020-116508RB-I00 and PID2020- 117498RB-I00. Daniel Caudevilla would like to express his thanks for grant PRE2018-083798, provided by the MICINN and the European Social Fund. Francisco Pérez Zenteno would also like to express his thanks for grant 984933, provided by CONACyT (Mexico)., Peer Reviewed, Postprint (author's final draft)

Objective: Build an Integral Health Care Pathway for the care of patients with lower limb amputation due to traumatic, vascular or diabetes mellitus causes, in order to implement the recommendations of the cpg for amputee patients and guarantee comprehensive health care for this population in Colombia. Methodology: This study is a strategy to improve health care. Carried out by a review of the Methodological Manual for the Development and Implementation of Comprehensive Health Care Pathway, then the development group was created. A process of prioritization and description of required individual interventions was developed based on health care. Evaluation of current care practice with focus groups, formulation of milestones and development of the intervention diagram. Results: 25 individual interventions were prioritized and characterized according to the responsible actor, target population and environment. Expected results in health, quality of service delivery, issues related to equity, as well as the perspective of patients and actors involved with care are shown. Indicators were built for monitoring and implementation of the pathway. Conclusion: With the previous results, the first Integral Health Care Pathway for the Lower Limb Amputee Patient was developed. It intends to guide the actors involved, when executing individual interventions for the diagnosis, treatment and rehabilitation, to impact outcomes in health and equity of this group., Objetivo: Construir uma Rota de Atenção Integral à Saúde do Paciente Amputado do Membro Inferior por causas traumáticas, vasculares ou diabetes mellitus, com a finalização de implementar as recomendações do gpc do paciente amputado e garantir a atenção integral na saúde desta población em Colômbia. Metodologia: Este estudo responde a uma estratégia para melhorar os cuidados de saúde. Foi realizada uma revisão do Manual Metodológico para o Desenvolvimento e Implementação de Rotas Integrais de Atenção à Saúde, criação do grupo de desenvolvimento da rota. Um processo de priorização e descrição das intervenções individuais necessárias foi desenvolvido com base na continuidade dos cuidados de saúde. Avaliação da prática assistencial atual com grupos focais, formulação de marcos e desenvolvimento do diagrama de intervenção. Resultados: 25 intervenções individuais foram priorizadas e caracterizadas de acordo com o ator responsável, população-alvo e ambiente. Determinação dos resultados esperados em saúde, qualidade da prestação de serviços, questões relacionadas a equidade, bem como a perspectiva de pacientes e atores envolvidos no atendimento. Foram construídos indicadores para o monitoramento e implementação da rota. Conclusão: Com os resultados anteriores, foi construída a primeira Rota de Atenção Integral à Saúde do paciente com amputação de membros inferiores por causas traumáticas e neurovasculares, com sua implementação, visando orientar os atores envolvidos na execução de intervenções individuais para a diagnóstico, tratamento e reabilitação, impactar os resultados em saúde e eqüidade dessa população., Objetivo: Presentar el estudio mediante el cual se construyó una ruta integral de atención en salud (RIAS) para la atención del paciente amputado de miembro inferior por causas traumática, vascular o diabetes mellitus, cuyo fin es implementar las recomendaciones de la Guía de práctica clínica del paciente amputado y garantizar la atención integral en salud de esta población en Colombia. Con la ruta se pretende orientar a los actores involucrados en la ejecución de intervenciones individuales para el diagnóstico, el tratamiento y la rehabilitación, e impactar en los desenlaces en salud y equidad de esta población. Metodología: Este estudio responde a una estrategia de mejoramiento de la atención en salud. Para esto, se revisó el Manual metodológico para la elaboración e implementación de las rias; se creó el grupo desarrollador de la ruta; se priorizaron y describieron las intervenciones en función del proceso continuo de atención en salud; se evaluó la práctica asistencial actual con grupos focales de pacientes y profesionales; se formularon los resultados esperados en el proceso de gestión y atención en salud (hitos), y se elaboró el diagrama de la ruta. Resultados: A partir de la Guía de práctica clínica se elaboraron 25 intervenciones individuales priorizadas y caracterizadas según el actor responsable, la población objetivo y el entorno. Para cada una de las intervenciones se presentan resultados esperados en salud, calidad de prestación de servicios, aspectos relacionados con la equidad, y la perspectiva de pacientes y actores involucrados con la atención. Se construyeron los indicadores para el seguimiento e implementación de la ruta. Conclusión: Se construyó la primera ruta integral de atención en salud del paciente con amputación de miembro inferior, de acuerdo con los lineamientos del manual del Ministerio de Salud y de la Protección Social.

Family Support is a transdisciplinary field made up of practices and knowledge from different areas, theories and approaches. This article strives to contribute to the development of this complex epistemological foundation by undertaking a review of the main theoretical frameworks. The relationship between the practice and theory of Family Support is analysed in the paper. A review of the ‘state of the art’ is undertaken, exploring both the role of wide-ranging social theory, and more specific psycho-social theories. Practical examples are provided to ground the analysis. Finally, the article proposes an integrated model proposed providing a critical and versatile approach to understanding different realities. Cross-national joint construction is encouraged to advance Family Support as both a theory and to provide a framework which guides both practice and policy.

Family Support is a transdisciplinary field made up of practices and knowledge from different areas, theories and approaches. This article strives to contribute to the development of this complex epistemological foundation by undertaking a review of the main theoretical frameworks. The relationship between the practice and theory of Family Support is analysed in the paper. A review of the ‘state of the art’ is undertaken, exploring both the role of wide-ranging social theory, and more specific psycho-social theories. Practical examples are provided to ground the analysis. Finally, the article proposes an integrated model proposed providing a critical and versatile approach to understanding different realities. Cross-national joint construction is encouraged to advance Family Support as both a theory and to provide a framework which guides both practice and policy.

© 2017 Elsevier B.V. Authors would like to acknowledge the CAI de Técnicas Físicas of the Universidad Complutense de Madrid for the metallic evaporations and sample etching. This work was partially supported by the Project MADRID-PV (Grant No. P2013/MAE-2780) funded by the Comunidad de Madrid and by the Spanish MINECO (Economic and Competitiviness Ministery) under grant TEC 2013- 41730-R Research by E. García-Hemme was also supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM). D. Pastor acknowledges the financial support to the grant EX-2010-0662 from the Spanish Science Ministry., The van der Pauw method to calculate the sheet resistance and the mobility of a semiconductor is a pervasive technique both in the microelectronics industry and in the condensed matter science field. There are hundreds of papers dealing with the influence of the contact size, nonuniformities and other second order effects. In this paper we will develop a simple methodology to evaluate the error produced by finite size contacts, detect the presence of contact resistance, calculate it for each contact, and determine the linear or rectifying behavior of the contact. We will also calculate the errors produced by the use of voltmeters with finite input resistance in relation with the sample sheet resistance., Ministerio de Economía y Competitividad (MINECO), Comunidad de Madrid, Campus de Excelencia Internacional (UCM-UPM), Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

The wine Common Market Organisation has established two concepts for recognizing the quality of wines in the European Union (EU). The first corresponds to the so-called Protected Designation of Origin (PDO), and the second to the Protected Geographical Indication (PGI). The set of Spanish PDOs includes the subset of Spanish DOs (Designation of Origin), which have been recognized as quality wines by Spanish authorities since 1932. Spain accounts for 67 DOs but, due to a lack of data, only 34 of them are suitable for carrying out our analysis. We will analyze the efficiency of this subset for the 2008, 2009 and 2010 seasons resorting to Data Envelopment Analysis (DEA) and using a new additive based efficiency measure known as BAM (Bounded Adjusted Measure). Since we are using panel data, we will also evaluate the productivity associated with this data set resorting to Malmquist indexes. Our results show that the efficiency behavior of the subset of Spanish DOs is uniform over the time periods analyzed and that productivity experiments only minor and irrelevant changes. They also show that three DOs are in a very good competitive position while another three DOs are in a very bad position. We end up suggesting some economic reasons for explaining these results.

The wine Common Market Organisation has established two concepts for recognizing the quality of wines in the European Union (EU). The first corresponds to the so-called Protected Designation of Origin (PDO), and the second to the Protected Geographical Indication (PGI). The set of Spanish PDOs includes the subset of Spanish DOs (Designation of Origin), which have been recognized as quality wines by Spanish authorities since 1932. Spain accounts for 67 DOs but, due to a lack of data, only 34 of them are suitable for carrying out our analysis. We will analyze the efficiency of this subset for the 2008, 2009 and 2010 seasons resorting to Data Envelopment Analysis (DEA) and using a new additive based efficiency measure known as BAM (Bounded Adjusted Measure). Since we are using panel data, we will also evaluate the productivity associated with this data set resorting to Malmquist indexes. Our results show that the efficiency behavior of the subset of Spanish DOs is uniform over the time periods analyzed and that productivity experiments only minor and irrelevant changes. They also show that three DOs are in a very good competitive position while another three DOs are in a very bad position. We end up suggesting some economic reasons for explaining these results.

We assess the degree of crystallinity by means of UV and visible Raman scattering measurements of Ti implanted Si layers with very high doses (10 15-5 × 1016 cm-2) subsequently annealed by nanosecond pulsed laser melting (PLM). We obtain ultraheavily impurified Si layers with Ti concentrations six orders of magnitude above the solid solubility limit in a layer several tens of nanometers thick. The PLM annealing processes are needed to recover the crystal quality and to keep the high Ti concentration required to form an intermediate band (IB). The UV Raman analysis permits us to evaluate the lattice crystallinity of the different implanted doses probing only the implanted region and points out Ti interstitial location in the host lattice in agreement with theoretical predictions for IB formation. By contrast, visible Raman spectra are only sensitive to the presence of a fully amorphized implanted layer as in the rest of the crystalline layers the probing depth far exceeds the implanted layer thickness and the signal is dominated by the undamaged Si. © 2011 IOP Publishing Ltd.

We have studied the laser thermal annealing LTA effects on single crystal GaP. The samples have been analyzed by means of Raman spectroscopy, glancing incidence x-ray diffraction GIRXD , and transmission electron microscopy TEM measurements. After LTA process, the Raman spectra of samples annealed with the highest energy density show a forbidden TO vibrational mode of GaP. This result suggests the formation of crystalline domains with a different orientation in the annealed region regarding the GaP unannealed wafer. This behavior has been corroborated by GIXRD measurements. TEM images show that the LTA produces a defective layer with disoriented crystalline domains in the surface. The depth of this defective layer increases with the energy density of LTA. The lack of crystallinity after LTA processes could be related with the high bond energy value of GaP. © 2009 American Institute of Physics.

We have investigated the pulse laser melting (PLM) effects on single crystal GaP. The samples have been studied by means of Raman spectroscopy, glancing incidence X-ray diffraction (GIRXD), van der Pauw and Hall effect measurements. After PLM process, the Raman spectra of samples annealed with the highest energy density show a forbidden TO vibrational mode of GaP. This suggests the formation of crystalline domains with a different orientation in the GaP PLM region regarding to the GaP unannealed region. This behavior has been corroborated by glancing incidence x-ray diffraction measurements. A slightly increase in the sheet resistivity and a suppression of the mobility in PLM samples have been observed in all the measured temperature range. Such annealing effects are a cause of great concern for intermediate band (IB) materials formation where PLM processes are required first, to recovery the lattice crystallinity after high dose ion implantation processes and second, to avoid impurities outdiffusion when the solid solubility limit is exceeded.

We present a Raman scattering and cathodoluminescence study of a set of InxAl1−xN/GaN epilayers with InN fractions around the lattice-matched composition. We observed the A1(LO) and InN-like E2 modes of the alloy, whose frequencies are in good agreement with theoretical predictions, but we were unable to detect the AlN-like E2 mode. The InN-like E2 mode did not exhibit noticeable frequency shifts in the studied samples. This is explained by the presence of residual strain in the pseudomorphic InxAl1−xN films. A luminescence peak that shifts to lower energies with an increasing InN fraction was observed at energies above the band edge of the GaN substrate. The cathodoluminescence peak energy is lower than expected, indicating a large band-gap bowing in these alloy layers.

The performance of a 2x2 all-fiber electrooptical switch is characterized in a system at up to 40 Gb/s. Error-free transmission is demonstrated. The device was also employed as a protection switch at 10 Gb/s in an installed fiber link., QC 20101015

We present Raman-scattering measurements on InxGa1−xN over the entire composition range of the alloy. The frequencies of the A1(LO) and E2 modes are reported and show a good agreement with the one-mode behavior dispersion predicted by the modified random-element isodisplacement model. The A1(LO) mode displays a high intensity relative to the E2 mode due to resonant enhancement. For above band-gap excitation, the A1(LO) peak displays frequency shifts as a function of the excitation energy due to selective excitation of regions with different In contents, and strong multiphonon scattering up to 3LO is observed in outgoing resonance conditions.

The concentrations of PCBs, DDTs, HCHs, HCB and OCS were determined in sediments and associated biota, both invertebrates (Physella acuta, Hirudo medicinalis, chironomid larvae, Hydrous pistaceus, Helochares lividus) and vertebrates (Rana perezi), in a temporary aquatic system, a rice field in the Ebro Delta (NE Spain). The qualitative and quantitative distribution of organochlorine compounds in sediments and aquatic biota has been explained by two mechanisms: equilibrium partitioning and/or biomagnification through the trophic web. Nevertheless, bioaccumulation processes are by far more complex, since several biotic and abiotic factors contribute to the observed pollutant loads in the organisms. In this respect, the biological characteristics of the organisms considered (e.g. species, age, lipid contents, feeding habits, etc.), as well as ecological factors (e.g. the habitat of the species and vertical distribution), have been shown to account for the organochlorine levels observed.

El proyecto Municipios Centinela, coordinado por el Ministerio de Salud a través de Programa Sistemas Municipales y financiado con los recursos de crédito del Banco Interamericano de desarrollo, es una fase más desagregada del Plan de Evaluación, el cual pretende ofrecer una guía para construir un sistema de información flexible y eficiente y dar respuesta en el corto y mediano plazo a las necesidades de información para la toma de decisiones en diferentes sectores del desarrollo. La presente investigación tuvo como propósito una rápida evaluación de los resultados de Sistema General de Seguridad Social en Salud (SGSSS), en el período comprendido entre 1995 y 1998, en localidades concretas con características similares al conjunto de los municipios colombianos clasificados en categorías 5 y 6, en lo que hace referencia a condiciones socioeconómicas, geográficas, demográficas e institucionales y de con un grado importante de marginación social. En el estudio se realizo la metodología de observatorios municipales, previa selección de municipios considerados centinela, articulándola a la metodología de marco lógico que incluye análisis de factores; todo el proceso fue enriquecido con el apoyo d e métodos de investigación cualitativa. El estudio se realizó simultáneamente en 14 municipios del país, ubicados en los departamentos de Antioquia, Atlántico, Boyacá, Caldas, Cauca, Cundinamarca, Huila, Nariño y Sucre. Este artículo presenta la metodología y los resultados obtenidos en 5 de los 14 municipios del estudio: Betulia y Yolombó de Antioquia, Toluviejo de Sucre, Piojó y Ponedera del Atlántico, los cuales correspondieron al convenio suscrito entre la Secretaría Ejecutiva del Convenio Andrés Bello (SECAB) y la Facultad Nacional de salud Pública de la Universidad de Antioquia.

The distributions of organochlorinated pesticides (DDTs, hexachlorobenzene -HCB- and lindane) and polychlorinated biphenyls (PCBs) have been determined in mussels from two bays of the Ebro Delta (Western Mediterranean) during the period 1980-1992. The data obtained enabled us to assess the fate and trends of these compounds in the area. A general decline in concentrations was observed for all organochlorinated pesticides during the studied period, reflecting a positive response to the existing regulations. However, the decline of PCBs was less evident, although a relative decrease of the low chlorinated congeners with time, possibly indicating a lack of recent inputs, was observed

Brain levels of 5-hydroxytryptamine (5-HT) and dopamine (DA) were determined along the first gonadotrophic cycle of Blattella germanica adult females. High-performance liquid chromatography (HPLC) combined with electrochemical (for DA) or fluorimetric (for 5-HT) detection was used. 5-HT levels did not show significant fluctuations, whereas DA levels showed characteristic ontogenetic changes which can be related to various events during the gonadotrophic cycle. The profile of DA levels in the first half of the cycle suggest an amine accumulation until days 2-3 (beginning of vitellogenesis) and a sudden drop occurring on day 4 (significant increase of oocyte length). In the second half of the cycle, DA levels show a peak on day 5 (full vitellogenesis) followed by a decrease on day 6 (termination of oocyte maturation) and a progressive increase up to days 7 (chorionation, ovulation, oviposition, ootheca formation) and 8 (24h after the formation of the first ootheca). These results suggest the possible involvement of DA in these events of the gonadotrophic cycle.

Na port.: Siguense los datos desconocidos para la vida de Lope de Vega publicados por primera vez en el "Homenaje a Menéndez y Pelayo", Na port.: é impreso á expensas del Excmo. Señor Marqués de Jérez de los Caballeros