17 research outputs found

    Role of heat and mechanical treatments in the fabrication of superconducting Ba0.6K0.4Fe2As2 ex-situ Powder-In-Tube tapes

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    Among the recently discovered Fe-based superconducting compounds, the (K,Ba)Fe2As2 phase is attracting large interest within the scientific community interested in conductor developments. In fact, after some years of development, critical current densities Jc of about 105 A/cm2 at fields up to more than 10 T have been obtained in powder in tube (PIT) processed wires and tapes. Here we explore the crucial points in the wire/tape fabrication by means of the ex-situ PIT method. We focus on scaling up processes which are crucial for the industrial fabrication. We analyzed the effects on the microstructure of the different heat and mechanical treatments. By an extensive microstructural analysis correlated with the transport properties we addressed the issues concerning the phase purity, the internal porosity and crack formation in the superconducting core region. Our best conductors with a filling factor of about 30 heat treated at 800 C exhibited Tc = 38 K the highest value measured in such kind of superconducting tape. The microstructure analysis shows clean and well connected grain boundaries but rather poor density: The measured Jc of about 3 x 10^4 A/cm2 in self-field is suppressed by less than a factor 7 at 7 T. Such not yet optimized Jc values can be accounted for by the reduced density while the moderate in-field suppression and a rather high n-factor confirm the high homogeneity and uniformity of these tapes

    Amphetamine modulates brain signal variability and working memory in younger and older adults

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    Better-performing younger adults typically express greater brain signal variability relative to older, poorer performers. Mechanisms for age and performance-graded differences in brain dynamics have, however, not yet been uncovered. Given the age-related decline of the dopamine (DA) system in normal cognitive aging, DA neuromodulation is one plausible mechanism. Hence, agents that boost systemic DA [such as d-amphetamine (AMPH)] may help to restore deficient signal variability levels. Furthermore, despite the standard practice of counterbalancing drug session order (AMPH first vs. placebo first), it remains understudied how AMPH may interact with practice effects, possibly influencing whether DA up-regulation is functional. We examined the effects of AMPH on functional-MRI–based blood oxygen level-dependent (BOLD) signal variability (SDBOLD) in younger and older adults during a working memory task (letter n-back). Older adults expressed lower brain signal variability at placebo, but met or exceeded young adult SDBOLD levels in the presence of AMPH. Drug session order greatly moderated change–change relations between AMPH-driven SDBOLD and reaction time means (RTmean) and SDs (RTSD). Older adults who received AMPH in the first session tended to improve in RTmean and RTSD when SDBOLD was boosted on AMPH, whereas younger and older adults who received AMPH in the second session showed either a performance improvement when SDBOLD decreased (for RTmean) or no effect at all (for RTSD). The present findings support the hypothesis that age differences in brain signal variability reflect aging-induced changes in dopaminergic neuromodulation. The observed interactions among AMPH, age, and session order highlight the state- and practice-dependent neurochemical basis of human brain dynamics

    Supplementary Material for: CBASP@home: Ein internetbasiertes Situationsanalysen-Training zur Stabilisierung des Therapieerfolgs nach stationärer Therapie für chronisch depressive Patienten

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    <b><i>Hintergrund: </i></b>Aufbauend auf einer ambulanten CBASP-Behandlung wurde ein stationäres multidisziplinäres Konzept zur Behandlung chronischer Depression entwickelt. Eine Pilotstudie zeigte positive Ergebnisse hinsichtlich der Wirkung dieses Konzepts, jedoch berichteten einige Patienten, dass die 12-wöchige Therapie zu kurz und die Zeit unmittelbar nach Entlassung schwierig sei. Daher wurde CBASP@home als ein internetbasiertes Situationsanalysen (SA)-Training zur Stabilisierung des erzielten Behandlungserfolgs konzipiert. CBASP@home ist eine 3-monatige Step-down-Onlineintervention. Die Patienten werden dabei unterstützt, die erlernten SA zu Hause fortzuführen und in den Alltag zu transferieren. An insgesamt 9 Terminen füllten die Patienten das SA-Formular über einen Sicherheitsserver aus und erhielten von ihrem stationären Psychotherapeuten zeitnah Rückmeldung. <b><i>Fallbericht: </i></b>In der vorliegenden Phase-I-Studie wurde die Akzeptanz und Durchführbarkeit von CBASP@home an 2 Einzelfällen untersucht. CBASP@home wurde von beiden Patienten sehr gut angenommen und als sinnvolle Unterstützung bewertet. Zudem konnte bei beiden Patienten eine zunehmende Leistungssteigerung in der SA-Durchführung bei gleichzeitig rückläufiger depressiver Symptomatik bis zur Remission beobachtet werden. <b><i>Schlussfolgerungen: </i></b>Die beiden Einzelfallauswertungen liefern Hinweise, dass CBASP@home Transferprozesse vom stationären Setting in den Alltag erleichtern, Behandlungserfolge beibehalten bzw. Rückfällen vorbeugen kann. Wenn sich diese positiven Erfahrungen in zukünftigen Studien bestätigen sollten, kann CBASP@home wesentlich zur Verbesserung der langfristigen Versorgung chronisch depressiver Patienten beitragen

    Crescimento inicial de duas cultivares de cafeeiro em diferentes regimes hídricos e dosagens de fertirrigação Initial growth of two coffee cultivars in different hydric regimes and fertigation dosages

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    O experimento foi conduzido no Centro Técnico de Irrigação (CTI), Universidade Estadual de Maringá (UEM), tendo como objetivo avaliar os efeitos de diferentes regimes hídricos (irrigado e não irrigado) e fertirrigação, combinados com diferentes doses de adubo para N (15; 30; 45 e 60 g m-1), P (3; 6; 9 e 12 g m-1) e K (15; 30; 45 e 60 g m-1), na fase de crescimento inicial de duas cultivares de café, na região noroeste do Paraná. Foram avaliadas as seguintes variáveis de crescimento da cultura: diâmetro de copa, altura de planta e número de ramos plagiotrópicos totais. Observou-se que a fertirrigação e a irrigação influenciaram no desenvolvimento inicial do cafeeiro, aumentando os valores de todas as variáveis avaliadas. A interação entre regimes hídricos e fertirrigação versus doses de NPK foi significativa para algumas variáveis de crescimento, porém esses resultados não apresentaram tendência comum, que permitisse constatar qual a dose mais indicada para cada regime hídrico na fase de crescimento inicial do cafeeiro.<br>The experiment was conducted at the Technical Center for Irrigation, Maringá State University. The objective was to evaluate the effects of different water regimes (irrigation and no irrigation) and fertilization-irrigation, combined with different manure doses for N (15; 30; 45 and 60 g m-1), P (3; 6; 9 and 12 g m-1) and K (15; 30; 45 and 60 g m-1), during the initial growth phase of two coffee cultivars, in the north-western region of the state of Paraná. The following culture growth variables were evaluated: top diameter, height of plant and number of total plagiotropic branches. Fertilization-irrigation and irrigation affected the initial development of coffee, increasing the values of all evaluated variables. Interaction between water regimes and fertilization-irrigation with NPK doses was significant for certain growth variables, however results didn't present a common trend, that would indicate which dose was adequate for each water regime during the initial growth phase of the coffee shrub

    Efeito da aplicação pré-colheita de cálcio na qualidade e no teor de nutrientes de manga 'Tommy Atkins' Quality and nutrient level of mango cv. 'Tommy Atkins' as affected by calcium application before harves

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    Com o objetivo de avaliar o efeito da aplicação pré-colheita de cálcio na qualidade e no teor de nutrientes de frutos de manga Tommy Atkins, foi realizado um experimento em um pomar comercial com dez anos de idade, localizado no município de Petrolina-PE. Foram avaliados sete tratamentos, sendo duas fontes comerciais de cálcio e três dosagens de cada fonte (5,8; 11,6 e 17,4 mmol L-1 de Ca na forma de Ca-quelatizado e 45,0; 90,0 e 135,0 mmol L-1 de Ca na forma de CaCl2.2H2O), além de um tratamento-controle. O delineamento experimental foi em blocos ao acaso, com quatro repetições. As aplicações dos tratamentos foram realizadas quinzenalmente, iniciadas quando os frutos apresentavam tamanho chumbinho (5 a 10 mm) e estenderam-se até duas semanas antes da colheita. Foram realizadas seis pulverizações de uma calda contendo os tratamentos, sendo que, em cada aplicação, foram fornecidos 12,5 L/planta de calda. Os frutos foram colhidos no estádio de maturação 2. Quarenta frutos, agrupados em lotes de dez, foram acondicionados em caixas de papelão com capacidade para 6 kg e submetidos ao armazenamento por 0; 20; 30 e 40 dias sob refrigeração (10.5&plusmn;1.0&deg;C e 90&plusmn;5% de UR). Depois de retirados da câmara fria, os frutos foram mantidos por cinco dias em sala de amadurecimento a 21&plusmn;1&deg;C e 60&plusmn;5% de UR. Foram determinados os teores de N, K, Ca e Mg na casca e na polpa dos frutos no lote equivalente ao tempo inicial de armazenamento e avaliada a incidência de colapso interno em todos os lotes. A aplicação de cálcio tanto na forma quelatizada quanto de sal solúvel aumentou as concentrações do nutriente na casca dos frutos. Aplicações de Ca-quelatizado mostraram-se eficientes em aumentar as concentrações de cálcio na polpa dos frutos, podendo contribuir para prevenir a ocorrência de colapso interno em curto período de armazenamento.<br>The effect of calcium on quality and nutrient level of mango cv. "Tommy Atkins" was studied when applied prior to harvest on a ten-year old orchard, in Petrolina, State of Pernambuco, Brazil. Three levels of two commercial calcium sources (5.8; 11.6 and 17.3 mmol L-1 of Ca as chelate Ca and 45.0; 90.0 and 135.0 mmol L-1 of Ca as the soluble salt CaCl2.2H2O), and a control treatment were evaluated, in a randomized complete block design with four replications. Calcium was applied every two weeks, starting at the fruit set stage (fruits 5 to 10 mm long) up to two weeks before harvest. Six sprayings of solutions containing the calcium treatments were applied providing 12.5 L of the solution/plant in each application. The fruits were harvested in the ripening stage 2. Forty fruits were grouped in four lots of ten, placed into cardboard boxes with capacity for 6 kg and stored for 0, 20, 30 and 40 days under refrigeration (10.5&plusmn;1.0&deg;C and 90&plusmn;5% RH). After removed from the cold chamber, the fruits were kept for five days in a ripening room at 21&plusmn;1&deg;C and 60&plusmn;5% RH. N, K, Ca and Mg contents in the flesh and skin were determined in the lot equivalent to the shortest time of storage and the incidence of internal breakdown was evaluated in all four lots. Calcium application in both chelate and soluble salt forms increased the nutrient contents in the skin. Applications of chelate Ca showed to be efficient in increasing the calcium contents in the fruit flesh, contributing to prevent the occurrence of internal breakdown in short storage periods
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