570 research outputs found

    Cryopreserved Embryo Disputes: Weighing Interests Regarding Genetic Parenthood

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    Ectomycorrhiza: phosphorus source specific economy and potential in resource partitioning

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    Many natural and anthropogenic soils are phosphorus (P) limited, as P is largely immobilized in forms of low bioavailability affecting the plant productivity. One of the strategies to overcome this shortage lies in the symbiosis of plants with mycorrhizal fungi that increases the plant P uptake of these hardly accessible sources in exchange for photoassimilates. Nevertheless, the required investment to acquire the free phosphate from various P sources increases with decreasing P source bioavailability, indicating a different carbon (C) sink potential. Ectomycorrhizae were shown to be able to acquire various P sources, but experimental evidence for their P source dependent C sink potential as well as for their role in resource partitioning for P is missing. The present study aimed to address following objectives: (i) to design a system to observe mycorrhizal mediated nutrient exchange (Study I); and to investigate (ii) whether the C investment from the host plant for the mycorrhizal mediated P derived from different P species is P source dependent (Study II); as well as the (iii) preferences of mycorrhizal plant to specific P sources from a mixed P pool (Study III). Following P sources were tested for the mycorrhizal mediated plant P uptake: PO43- (oP), the primary mineral apatite (AP; Study II) or hydroxyapatite (HAP; Study III), the organic P species (Porg) phytic acid (Phy; Study II) or adenosine monophosphate (AMP; Study III), and goethitebound PO43- (gP) as secondary mineral-P adsorption complex. The practical experience made in Study I revealed that, compared with the in vitro culture system, the construction and maintenance of the axenic rhizotrone and the mesocosm culture systems are less complicated and time consuming and at the same time more robust and very versatile systems that are also suitable for greenhouse conditions. In Study II a P source dependent trend in exchange of host C for ectomycorrhizal mediated P in roots was determined. The exchange of C for P in ectomycorrhizal roots of AP and gP treatments were of similar magnitude and could result from the applying the same mechanism, the exudation of LMWOAs and hyphal growth to acquire mineral P sources (mineral P effect). In contrast, the readily available P source oP, the soluble Phy, as well as the complete P limitation turn the ectomycorrhizal plant into a system of C retention in the mycorrhizal root interface. These results indicate a trend that the C allocation into the belowground is P source specific, which can have an impact on the C balance in soils of natural and anthropogenic ecosystems. The results of Study III show that an ectomycorrhizal plant is able to utilize all provided P sources via its mycorrhizal fungal associate. The acquisition timing was determined by the most bioavailable P sources, with oP and AMP over HAP and gP, and a mixed P pool over single P source. In contrast, the magnitude was defined by the amount of supplied P source and provision of additional nitrogen, hence AMP over oP and gP, as well as by P source complexity, with gP as the least favourable P form. Nevertheless, these results provide evidence that an ectomycorrhiza has the potential to occupy fundamental niches of various P sources differing in their bioavailability, indicating that being a generalist in P nutrition can facilitate adaptation to various nutritional settings in soil

    Variations of the geomagnetic dipole magnitude over the past 400 My

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    The international bank of the virtual dipole moment data supplemented by the values from more recent publications is used as the basis for an analysis of the behavior of the virtual dipole moment values over the last 400 My. The results obtained revealed a positive linear trend from 4.1 × 1022 to 5.7 × 1022 A m2 during the last 400 My. Against the background of the linear increase, fluctuations with a periodicity of about 40 My were observed. In the Phanerozoic time, minimums within the intervals of 340–370, 290–300, 240–270, 190–210, 165-140 (chrons M17-M43), 130-120 (chrons M2-M10), 100–110 (chron 34), 75–85 (chron C33 and the beginning of chron C34), 70-60 (chrons C31-C27), and 40-15 (chrons C18-C5AD) My B.P. are found. The distribution of the virtual dipole moment is strictly related to the distribution of the ancient geomagnetic field and may be taken into consideration when modeling the magnetization of the inversive magnetic layer of the ocean

    Oil & Gas accounting

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    Originally published by: Touche Ross & Co.

    Effects of pruning a temperate mangrove forest on the associated assemblages of macroinvertebrates

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    Mangrove forests around the world are being impacted by development in adjacent land and water areas. An after-control-impact study was undertaken to assess the effects of mangrove forest pruning on the associated benthic macroinvertebrate fauna. Pruning, undertaken 5 years before our sampling period, reduced the height of the forest canopy from 5 m to 1 m. Macrobenthic assemblages were sampled in September 2000 and January 2001 from two randomly selected sites within the pruned section of forest, and two sites in each of two control locations in the same forest. Assemblage composition in the pruned and undisturbed mangrove forests was not significantly different, nor were there significant differences in variability between the two areas. Similarity matrices for assemblages based on higher taxonomic groups and molluscs were highly correlated with similarity matrices for all taxa, indicating the utility of more rapid forms of assessment in this habitat. The results suggest that although short-term impacts may have occurred, no impact on macroinvertebrate assemblages was evident 5 years after the pruning

    Herramientas para Contribuir a la Gestión Sustentable del Agua en Latinoamérica

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    Estas 5 herramientas son una muestra de los conocimientos compartidos y transferidos entre los Puntos Focales Nacionales y los Centros de Excelencia de RALCEA, en los 7 encuentros de desarrollo de capacidades realizados. Consideramos de especial importancia a éstas herramientas, en tanto que aportan una base para la continuidad de RALCEA y a la atención a temas que fueron identificados como clave por parte de los Puntos Focales Nacionales: Principios de la GIRH; Gestión de Aguas Subterráneas; Identificación de Actores y Gestión a nivel de cuencas; Educación a nivel de las escuelas como estrategia para el cambios; e instrumentos para la gestión de una red como forma de apoyar la continuidad y sustentabilidad de RALCEA. Esperamos que los miembros de RALCEA, así como otros profesionales y representantes de grupos de interés del sector del agua encuentren un importante valor y apoyo mediante el uso de estas herramientas, como un pequeño aporte a las metas de desarrollo que le dan sentido a RALCEAJRC.H.1-Water Resource

    Manual para el diseño, realización, evaluación y monitoreo de actividades de desarrollo de capacidades

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    Fundamentalmente, el desarrollo de capacidades es acerca del cambio. Los resultados esperados consisten generalmente en qué medida las personas realizan su trabajo de manera diferente. Para hacerlo, necesitan mayores conocimientos, burocracias u organizaciones que les animen a hacerlo, y cambios en las reglas y normas informales que motiven cambios en el comportamiento. Ahora es comúnmente aceptado que el conocimiento y la capacidad deben ser concebidas y dirigidas a varios niveles distintos, pero interconectados, incluyendo tanto a los individuos (con sus conocimientos, experiencia, habilidades y actitudes), las organizaciones (que operan a través de procedimientos, rutinas, la gestión del conocimiento y de incentivos sistemas) y las instituciones del sector y el "entorno propicio" (marcos legales, fiscales, la política y los marcos administrativos) y la sociedad civil . Los esfuerzos de desarrollo de capacidades serán tanto más efectivos cuando se consideren y profundicen estos aspectos, que requieren una profunda comprensión del contexto actual (el punto de partida), la visión de los resultados a alcanzar, y el diseño de una estrategia para lograrlo. Todos estos hitos deberán también considerar indicadores de cambios y mecanismos de monitoreo y evaluación, que también deberán contar con el necesario presupuesto para realizarse. Es responsabilidad de las organizaciones de desarrollo de capacidades evaluar sus impactos, pero esto no será factible sin una profunda compresión de la complejidad del desarrollo de capacidades y la gestión del conocimiento. Esperamos que este manual brinde aspectos prácticos que ayuden en el diseño de algunas de las tantas actividades que se pueden hacer en el marco del desarrollo de capacidades, y que dirijan la mirada hacia otras áreas, como el monitoreo y la evaluación que son tan necesarias como las actividades en sí mismas.JRC.H.1-Water Resource

    In Vivo Yeast Cell Morphogenesis Is Regulated by a p21-Activated Kinase in the Human Pathogen Penicillium marneffei

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    Pathogens have developed diverse strategies to infect their hosts and evade the host defense systems. Many pathogens reside within host phagocytic cells, thus evading much of the host immune system. For dimorphic fungal pathogens which grow in a multicellular hyphal form, a central attribute which facilitates growth inside host cells without rapid killing is the capacity to switch from the hyphal growth form to a unicellular yeast form. Blocking this transition abolishes or severely reduces pathogenicity. Host body temperature (37°C) is the most common inducer of the hyphal to yeast transition in vitro for many dimorphic fungi, and it is often assumed that this is the inducer in vivo. This work describes the identification and analysis of a new pathway involved in sensing the environment inside a host cell by a dimorphic fungal pathogen, Penicillium marneffei. The pakB gene, encoding a p21-activated kinase, defines this pathway and operates independently of known effectors in P. marneffei. Expression of pakB is upregulated in P. marneffei yeast cells isolated from macrophages but absent from in vitro cultured yeast cells produced at 37°C. Deletion of pakB leads to a failure to produce yeast cells inside macrophages but no effect in vitro at 37°C. Loss of pakB also leads to the inappropriate production of yeast cells at 25°C in vitro, and the mechanism underlying this requires the activity of the central regulator of asexual development. The data shows that this new pathway is central to eliciting the appropriate morphogenetic response by the pathogen to the host environment independently of the common temperature signal, thus clearly separating the temperature- and intracellular-dependent signaling systems

    Mapeo de actores y desarrollo de capacidades para la gestión del agua Casos de estudio en Latinoamérica

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    Los casos de estudio aquí presentados constituyen elementos demostrativos que destacan los resultados de la estrategia llevada a cabo por la Coordinación del Eje Temático Mapeo de Actores para el diseño e implementación de las actividades de desarrollo de capacidades identificadas. La propuesta metodológica basada en la identificación y diseño de acciones de capacitación orientadas por la demanda es un proceso de mejora continua. De él resulta que el diseño para cada actividad sea único, a medida. Los casos de estudios tratan de 1)Fortalecimiento de instituciones locales para la gestión integrada de los recursos hídricos de la cuenca, 2)Estrategias para el manejo, monitoreo y gestión de acuíferos, 3)Retos de la apropiación de tecnologías en el sector hídrico de Latinoamérica, 4)Mapeo de actores y gestión de cuencas hidrográficas, 5)Consejos de recursos hídricos de cuenca y 6)La participación de los actores en la gestión del agua.JRC.H.1-Water Resource

    Avaliação do custeio por absorção da diálise peritoneal e hemodiálise sob o ponto de vista do prestador de serviço (bottom up), relacionado ao repasse do Sistema Único de Saúde e da Saúde Suplementar (top down): análise de um registro por três anos

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    Health issues, especially those concerning the financing of its actions and services, raise great concerns in the most diverse segments of society. The International Nephrology Society emphasizes that chronic kidney disease affects 850 million people worldwide. If not addressed, by 2040 it is projected ro be the fifth most common cause of years of life lost. The estimated annual expenditure on Renal Replacement Therapy in Brazil is R2.2billion.Theobjectiveofthestudywastoevaluatethecostofabsorptionofperitonealdialysis(PD)andhemodialysis(HD)fromthepointofviewoftheserviceproviderandcomparewiththetransferoftheUniqueHealthSystem(SUS)andSupplementaryHealth(SS).AstudywascarriedoutfromtheperspectiveoftheserviceproviderfromJanuary2013toDecember2016inaprivateunitthatprovidesHDandPDservicesforbothhealthsystems.Thevariablesanalyzedwere:permanentassets,personnelexpenses,medicalsupplies,taxexpenses,laborcharges.ThedatawerearrangedinExcelspreadsheetsandananalysiswasperformedusingtheInput−OutputMatrixmethod.27,666HDsessionswereheldin2013,26,601in2014,27,829in2015and28,525in2016.Therewere264PDpatientsin2013,348in2014,372in2015and300in2016.Thetheoreticalaveragecostfortheserviceproviderwas:HDsessionintheroomforpatientswithhepatitisB(R2.2 billion. The objective of the study was to evaluate the cost of absorption of peritoneal dialysis (PD) and hemodialysis (HD) from the point of view of the service provider and compare with the transfer of the Unique Health System (SUS) and Supplementary Health (SS). A study was carried out from the perspective of the service provider from January 2013 to December 2016 in a private unit that provides HD and PD services for both health systems. The variables analyzed were: permanent assets, personnel expenses, medical supplies, tax expenses, labor charges. The data were arranged in Excel spreadsheets and an analysis was performed using the Input-Output Matrix method. 27,666 HD sessions were held in 2013, 26,601 in 2014, 27,829 in 2015 and 28,525 in 2016. There were 264 PD patients in 2013, 348 in 2014, 372 in 2015 and 300 in 2016. The theoretical average cost for the service provider was: HD session in the room for patients with hepatitis B (R981.10), for seronegative (R197.99),forseropositivewithhepatitisC(R197.99), for seropositive with hepatitis C (R238.30) and for DP (R3260.93)monthly.ComparedtotheSUStransfer,itwasnotedthatforpatientswithhepatitisBtherewasadifferenceof−269.73260.93) monthly. Compared to the SUS transfer, it was noted that for patients with hepatitis B there was a difference of -269.7%, seronegative -2.0%, seropositive for hepatitis C +10.2% and for DP -29.8%. Compared with the transfer of SS to patients with hepatitis B it was -50.2%, seronegative +56.27%, seropositive for hepatitis C +64.54% and for DP +48.26%. It was concluded that, when evaluating the cost of dialysis therapy from the perspective of the service provider related to the transfer of SUS, it is observed that, in percentage, there is a constraint on the cost in both HD and PD.Os assuntos da saúde, principalmente aqueles sobre o financiamento de suas ações e serviços, despertam grandes preocupações nos mais diversos segmentos da sociedade. A Sociedade Internacional de Nefrologia enfatiza que a doença renal crônica afeta 850 milhões de pessoas no mundo. Se não for abordada, projeta-se que até 2040 seja a quinta causa mais comum de anos de vida perdidos. O gasto anual estimado com Terapia Renal Substitutiva no Brasil é de 2,2 bilhões de reais. O objetivo do estudo foi avaliar o custeio por absorção da diálise peritoneal (DP) e hemodiálise (HD) sob o ponto de vista do prestador de serviço e comparar com o repasse do Sistema Único de Saúde (SUS) e da Saúde Suplementar (SS). Realizou-se um estudo, sob a perspectiva do prestador de serviço no período de janeiro de 2013 a dezembro de 2016 em uma unidade privada que fornece serviços de HD e DP para os dois sistemas de saúde. As variáveis analisadas foram: ativo permanente, despesas com pessoal, materiais médicos, despesas tributárias, encargos trabalhistas. Os dados foram dispostos em planilhas de Excel e realizada uma análise utilizando o método Matriz Insumo Produto. Foram realizadas 27.666 sessões de HD em 2013, 26.601 em 2014, 27.829 em 2015 e 28.525 em 2016. Observou-se 264 pacientes em DP em 2013, 348 em 2014, 372 em 2015 e 300 em 2016. O custo médio teórico para o prestador de serviço foi: sessão de HD na sala para pacientes com hepatite B (R981,10), para soronegativos ( R197,99),parasoropositivoscomhepatiteC(R197,99), para soropositivos com hepatite C (R238,30) e para DP (R$3260,93) mensal. Comparado ao repasse do SUS, notou-se que para pacientes com hepatite B houve uma diferença de -269,7%, soronegativos - 2,0%, soropositivos para hepatite C +10,2% e para DP -29,8%. Comparando com o repasse da SS para pacientes com hepatite B foi de -50,2%, soronegativos +56,27%, soropositivos para hepatite C +64,54% e para DP +48,26%. Concluiu-se que, quando avaliado o custo da terapia dialítica sob a perspectiva do prestador de serviço relacionado ao repasse do SUS observa-se que, percentualmente, há um constrangimento do custo tanto na HD quanto na DP
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