9,271 research outputs found
Breaking Pseudo-Rotational Symmetry through Metric Deformation in the Eckart Potential Problem
The peculiarity of the Eckart potential problem on (the upper
sheet of the two-sheeted two-dimensional hyperboloid), to preserve the
-fold degeneracy of the states typical for the geodesic motion there,
is usually explained in casting the respective Hamiltonian in terms of the
Casimir invariant of an so(2,1) algebra, referred to as potential algebra. In
general, there are many possible similarity transformations of the symmetry
algebras of the free motions on curved surfaces towards potential algebras,
which are not all necessarily unitary. In the literature, a transformation of
the symmetry algebra of the geodesic motion on towards the
potential algebra of Eckart's Hamiltonian has been constructed for the prime
purpose to prove that the Eckart interaction belongs to the class of Natanzon
potentials. We here take a different path and search for a transformation which
connects the dimensional representation space of the pseudo-rotational
so(2,1) algebra, spanned by the rank- pseudo-spherical harmonics, to the
representation space of equal dimension of the potential algebra and find a
transformation of the scaling type. Our case is that in so doing one is
producing a deformed isometry copy to such that the free motion
on the copy is equivalent to a motion on , perturbed by a
interaction. In this way, we link the so(2,1) potential algebra concept of the
Eckart Hamiltonian to a subtle type of pseudo-rotational symmetry breaking
through metric deformation.Comment: misprints are correcte
Implementación del Monitoreo de opciones de Agricultura Sostenible Adaptada al Clima (ASAC): Seguimiento a su adopción e impactos en el TeSAC de Santa Rita, Honduras. - Reporte de Actividad
Este documento presenta los resultados de la implementación del Marco de monitoreo multinivel sobre Agricultura Sostenible Adaptada al Clima (ASAC), en el TeSAC de Santa Rita en Honduras. Este monitoreo ha permitido generar evidencia sobre la adopción de prácticas y tecnologías agrícolas viables y climáticamente inteligentes implementadas en el territorio. Además, otro objetivo del monitoreo fue evaluar el efecto que tiene la implementación de prácticas ASAC en la seguridad alimentaria, los medios de vida de los hogares y varias dimensiones de género. Para ello se recopiló información sobre las características socioeconómicas de 143 hogares y 248 agricultores (120 hombres y 128 mujeres), su percepción ante el efecto de eventos climáticos y la implementación de prácticas ASAC, entre otros aspectos
Exploring EU food safety notifications on Agro-food imports: Are Mediterranean partner countries discriminated?
[EN] Limited capacity to comply with standards and controls has constrained the trade opportunities generated by bilateral agreements and preferences given to developing countries such as those belonging to the Mediterranean region. Specifically, in this paper we focus on the implementation of a specific type of Non-Tariff Measures that includes food safety concerns by the European Union. This is carried out through exploring some of the influencing factors on food standard enforcement in the EU, which is a major importer of agro-food products from developing countries. The issue at stake emerges on the possible rationale behind the border notifications on food imports -which can be the result of the management of specific risks- but beyond that by considering the reputation of the product or of the country of origin. We explore the hypothesis that the past border notifications affect current notifications, in other words, they affect current decisions on the implementation of food standards by the EU. Methodologically, notifications are extracted from those reported on the Rapid Alert System for Feed and Food (RASFF), and count data models are used to account for the over-dispersion existing in them. The results of the paper support the hypothesis that previous food notifications may slightly affect current notifications; nevertheless this effect seems to be less relevant for products of interest for Mediterranean Partner Countries. Hence, we cannot identify a pro or anti Mediterranean bias in the way that food safety controls are implemented at the EU borders.The authors wish to thank Josep Domènech and Lorena Tudela for helpful insights and assistance in implementing the algorithm for the transformation of RASFF data into computable data. The authors acknowledge the support received from the projects AGL2012–39793-C03–02, funded by the Ministry of Economy and Competitiveness (Spain) and the Univeristat Politècnica de València (PAID 06-12).Taghouti, I.; Martinez Gómez, VD.; García Alvarez-Coque, JM. (2015). Exploring EU food safety notifications on Agro-food imports: Are Mediterranean partner countries discriminated?. International Journal of Food and Agricultural Economics. 3(2):15-29. http://hdl.handle.net/10251/102162S15293
Commerce alimentaire et mesures non tarifaires dans la Méditerranée
[Otros] Depuis les dernières décennies, les pays du Sud et de l'Est de la Méditerranée suivent un processus de libéralisation progressive des échanges. Comme conséquence de ce processus, l'importance et l'intérêt des mesures non tarifaires a augmenté. Le but de cet article est de considérer les facteurs sous-jacents pour l'application des mesures non tarifaires au-delà des préoccupations spécifiques en matière de sécurité alimentaire. Pour ce faire, nous examinons l'importance de deux hypothèses qui fournissent une explication aux MNT dans les pays méditerranéens. La première est l'«effet de réputation» ou l'influence du passé historique des notifications sur les refus à la frontière. La deuxième fait référence à l'hypothèse de la politique de substitution ou compromis entre les mesures non tarifaires et les tarifs douaniers. Ces deux points de vue visent à donner une image de la mise en oeuvre et la situation des MNT dans le commerce alimentaire méditerrannéen. Les deux hypothèses suggèrent qu'il existe des facteurs économiques et politiques qui affectent la mise en oeuvre des MNT.[EN] Since the last decades, Southern and Eastern Mediterranean Countries (SEMCs) are following a process of progressive trade liberalization. As a consequence of such process, the significance and interest on Non-Tariff Measures (NTMs) has increased. The aim of this paper is to discuss the underlying factors affecting the implementation of NTMs. NTMs include specific food safety concerns. However, there could also be economic and political reasons affecting the frequency of implementation of food safety measures (border alerts). We thus explore the significance of two hypotheses that provide an explanation of NTMs in Mediterranean countries. The first one is the ¿reputation effect¿ or the influence of past history of notifications on border rejections. The second one refers to the policy substitution hypothesis or the trade-off between NTMs and tariffs. These two approaches intend to give an overview of the implementation of NTMs situation across Mediterranean trade food area. Both suggest that there are economic and political factors affecting NTM implementation.The authors are grateful for the support received from the Universitat Politècnica de València, (PAID-06-12).García Alvarez-Coque, JM.; Tudela Marco, L.; Martinez Gomez, VD. (2015). Mediterranean food trade and Non-Tariff Measures. Options Mediterraneennes. Serie A: Seminaires Mediterraneens. Serie A(111):113-125. http://hdl.handle.net/10251/150319S113125Serie A11
Multi-actor arrangements for farmland management in Eastern Spain
[EN] Farmland abandonment is common in the southern EU countries. This complex phenomenon has a set of interlinked causes and consequences, among the latter the undermining of farmers' cooperatives role as supply aggregators. The paper discusses a multi-actor farmland consolidation model that avoids some of the drawbacks identified by literature to some models of land mobilization, mostly transaction and agency costs. This model consists on a local-based strategy of common land management, led by a cooperative and supported by a set of external agents. As empirical evidences, we show the attitudes of cooperatives' managers surveyed towards common land management and present a case study implementing this multi-actor model. This piece of evidence shows that strengthening social capital is crucial to the success of these social innovation experiences.The authors are grateful for the financial support of Ministry of Science and Innovation/European Regional Development Fund, Spain. Project "Strengthening innovation policy in the agri-food sector" (RTI2018-093791-B-C22). Data of land management practices in agricultural cooperatives were obtained with the support of Catedra de Estructuras Agrarias UPV-Generalitat Valenciana. They are also grateful to the journal editor and the anonymous reviewers for their constructive comments and suggestions which significantly improved this paper.García Alvarez-Coque, JM.; Martinez Gomez, VD.; Tudela-Marco, L. (2021). Multi-actor arrangements for farmland management in Eastern Spain. Land Use Policy. 111:1-9. https://doi.org/10.1016/j.landusepol.2021.1057381911
Barriers to accessing maternal healthcare among ethnic minority women in Western China: a qualitative evidence synthesis.
Quantitative evidence suggests that ethnic disparities in maternal healthcare use are substantial in Western China, but the reasons for these remain under-researched. We undertook a systematic review of English and Chinese databases between January 1, 1990 and February 23, 2018 to synthesize qualitative evidence on barriers faced by ethnic minority women in accessing maternal healthcare in Western China. Four English and 6 Chinese language studies across 8 provinces of Western China and 13 ethnic minority groups were included. We adapted the 'Three Delays' framework and used thematic synthesis to categorize findings into six themes. Studies reported that ethnic minority women commonly held traditional beliefs and had lower levels of education, which limited their willingness to use maternal health services. Despite the existence of different financial protection schemes for services related to delivery care, hospital birth was still too costly for some rural households, and some women faced difficulties navigating reimbursement procedures. Women who lived remotely were less likely to go to hospital in advance of labour because of difficulties in arranging accommodation; they often only sought care if pregnancies were complicated. Poor quality of care in health facilities, particularly misunderstandings between doctors and patients due to language barriers or differences in socio-economic status, and clinical practices that conflicted with local fears and traditional customs, were reported. The overall evidence is weak however: authors treated different ethnicities as if they belonged to one homogeneous group and half of the studies failed in methodological rigour. The current evidence base is very limited and poor in quality, so much more research elucidating the nature of 'ethnicity' as a set of barriers to maternal healthcare access is needed. Addressing the multiple barriers associated with ethnicity will require multi-faceted solutions that adequately reflect the specific local context
Manual de implementación de prácticas de Agricultura Sostenible Adaptada al Clima (ASAC). Experiencias de los TeSAC de Guatemala y Honduras.
Este manual recoge algunas de las prácticas agropecuarias implementadas en el TeSAC de Olopa (en las comunidades de El Guayabo, Nochán, Tituque (Caserío Tishmuntique y Tuticopote abajo), así como en el TeSAC de Santa Rita, (en las comunidades de Tierra Fría, La Casita, Aldea nueva, Queseras y Villanueva).
Dichas prácticas son el resultado de un esfuerzo entre las comunidades mencionadas, CCAFS y sus socios implementadores tanto en Guatemala (la Asociación Regional Campesina Ch'orti' - ASORECH), como en Honduras (la Comisión de Acción Social Menonita - CASM)
Falling aid for reproductive, maternal, newborn and child health in the lead-up to the COVID-19 pandemic.
Summary box
Greater investment in reproductive, maternal, newborn and child health (RMNCH) is needed to mitigate the negative effects of COVID-19 and avoid a reversal of recent gains in RMNCH coverage and outcomes.
Aid for RMNCH as a whole fell by 6% between 2017 and 2018 and only increased by 2% in 2019; over the same 2-year period, aid for the reproductive health of non-pregnant women fell by 25%.
Volatile and falling aid for RMNCH may have rendered RMNCH systems more fragile in the 2 years preceding the COVID-19 pandemic.
We encourage everyone—academics, advocates and policy makers—to explore and exploit the Muskoka2 aid for RMNCH dataset and other aid datasets, as part of efforts to improve RMNCH outcomes
Acuerdos comerciales, competitividad y crisis en la citricultura valenciana
[ES] La campaña 2018-2019 se ha convertido para el sector citrícola valencia-no en una de las peores de su historia reciente. El malestar acumulado en algunos de los grupos de productores más afectados ha provocado incluso una inédita movilización ciudadana de protesta. El elemento detonante ha sido el nuevo acuerdo comercial entre la UE y los países sudafricanos. Este acuerdo se inscribe en la progresiva liberalización de las importaciones citrícolas por parte de la UE. En este nuevo escenario, las debilidades en materia de estructura, organización y calidad comercial del sector lo hacen especialmente vulnerable en campañas abundantes y accidentadas como ésta. Las consecuencias pueden ser dramáticas para muchos operadores si no se producen cambios profundos en las estrategias competitivas del sector, que hasta la fecha carecen de un enfoque integrador y ambicioso.Compes López, R.; García Alvarez-Coque, JM.; Martinez Gomez, VD. (2019). Acuerdos comerciales, competitividad y crisis en la citricultura valenciana. Distribución y consumo. 158(3):38-46. http://hdl.handle.net/10251/165520S3846158
USO DE LA ELECTROMIOGRAFÍA DE SUPERFICIE COMO MÉTODO DE EVALUACIÓN EN LA MECÁNICA DEGLUTORIA.
INTRODUCCION con el paso del tiempo la electromiografía ha logrado avances científicos en la evaluación de las funciones estomatognáticas, determinando las características particulares de los medios tecnológicos para la toma del examen, en el análisis e interpretación de resultados, demostrando la pertinencia objetiva de la evaluación electromiografía en la función oral faríngea, sin embargo a la actualidad se evidencia escases de protocolos de evaluación que permite guiar y recoger las señales necesarias para una confirmación diagnóstica en trastornos deglutorios, precisando diferentes mecanismos para la evaluación individual y grupal de los músculos que participan en las funciones deglutorias. METODOS la investigación recolecto información de diferentes bases de datos haciendo uso de descriptores tales como: electromiografía, deglución y disfagia; aplicando el método descriptivo, apoyado en un matriz de análisis. RESULTADOS se realizó búsqueda en diferentes bases de datos y revistas científicas, obteniendo un total de 360 artículos de los cuales según los criterios de inclusión y exclusión definidos se incluyen el presente artículo 14 textos, los cuales aplican electromiografía en la deglución. ANALISIS Y DISCUSION se encontró mayor aplicabilidad de la electromiografía en países como España con 28,57% y a nivel nacional se evidenció solo un 21,42% de artículos relacionados con la temática. CONCLUSIONES se sugiere la continuar en la búsqueda de evidencia que permita emplear la electromiografía como un método diagnóstico
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