4,216 research outputs found
Traceability statement for the determination of total chromium fraction in serpentine soils by atomic absorption spectrometry
The purpose of this work is to contribute for the metrological traceability statement of chemical measurements. Traceability statement for total chromium mass fraction in serpentine soils was developed. Accordingly, the quantity values requiring a high degree of control are calibration and quality control standard solutions, matrix certified reference material and the calibration curve model fit
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Understanding the coach-coachee-client relationship: a conceptual framework for executive coaching
Objectives: There is a need for a more comprehensive understanding of how coaching processes psychologically operate. This paper presents the findings from a study aimed to characterise the coaching process experience and to identify how specific experiences contribute to coaching outcomes. Design: A qualitative design was adopted. Data was analysed by Interpretative Phenomenological Analysis (Smith, 2008). Method: Data was collected from 10 participants, this included coaches (N = 4), coachees (N = 5) and one commissioner, three times along the coaching process. A total of 30 interviews were undertaken. Findings: Coaching outcomes can be generated by three essential mechanisms: Projection of Future Self; Perspectivation of Present Self; and Confirmation of Past/Present Self. Each mechanism’s name represents a particular effect on coachee’s self and may evolve diverse coaching behaviours. Although they all can be actively managed to generate sustainability of outcomes, each mechanism tends to contribute differently to that sustainability. Conclusion: The study provides a comprehensive understanding of the different methodological and experiential ingredients of the coaching process and its implications. While most coaching research is focused on identifying coaching results based on a retrospective analysis, this is one of the first studies accompanying longitudinally the coaching process and capturing an integrative understanding of its dynamics. Moreover, the study provides evidence of how coaching can differently deliver sustainable outcomes and be used as a valuable developmental tool in organisations. The study contributes to our understanding of theory building and raises questions for further research on the uniqueness of coaching interventions
Monitoring Hg and Cd contamination using red swamp crayfish (Procambarus clarkii): implications for wetland food chain contamination
Environmental pollution is one of the most serious causes of degradation of Mediterranean wetlands. Mercury (Hg) and cadmium (Cd) are of particular concern due to biomagnification. Here, we used red
swamp crayfish (Procambarus clarkii) to monitor the spatial and temporal patterns of these two metals in a Portuguese rice field system. We sampled the crayfish in three different sites and three different time periods in the Sado River Basin (Portugal). We measured temperature, pH, total dissolved solids and conductivity in the water. Hg and Cd were measured in the crayfish abdominal muscle tissue and exoskeleton. In muscle, a spatial pattern was found for the accumulation of Cd while for Hg, only a temporal pattern emerged. The spatial pattern for Cd seemed to reflect the mining history of the sites, whereas the temporal pattern for Hg seemed related to the flooding of rice fields. We suggest that this flooding process increases Hg bioavailability
Indução da germinação in vitro de grãos de pólen de Musa velutina.
O objetivo deste trabalho foi determinar os meios de cultura mais adequados para o estabelecimento e germinação in vitro de grãos de pólen de M. velutina, onsiderando a ausência de trabalhos na literatura cientÃfica abordando este tema.bitstream/CPAF-RO-2010/14512/1/106-musavelutina.pd
Palynological study of the endemic woody sonchus fron the flora of Madeira: a morphological and molecular approach
info:eu-repo/semantics/publishedVersio
Amygdala-ventral striatum circuit activation decreases long-term fear
In humans, activation of the ventral striatum, a region associated with reward processing, is associated with the extinction of fear, a goal in the treatment of fear-related disorders. This evidence suggests that extinction of aversive memories engages reward-related circuits, but a causal relationship between activity in a reward circuit and fear extinction has not been demonstrated. Here, we identify a basolateral amygdala (BLA)-ventral striatum (NAc) pathway that is activated by extinction training. Enhanced recruitment of this circuit during extinction learning, either by pairing reward with fear extinction training or by optogenetic stimulation of this circuit during fear extinction, reduces the return of fear that normally follows extinction training. Our findings thus identify a specific BLA-NAc reward circuit that can regulate the persistence of fear extinction and point toward a potential therapeutic target for disorders in which the return of fear following extinction therapy is an obstacle to treatment.National Institute of Mental Health (U.S.) (R01 MH084966)United States. Army Research OfficeUnited States. Defense Advanced Research Projects Agency (grant W911NF-10-1-0059
Contamination by heavy metals in aquatic trophic webs: the case of otter and red-swamp crayfish
In a detailed scanning electron microscope study of the recrystallisation of an IF steel it was observed that the new grains went through an equiaxed stage which became elongated along the rolling direction and then became equiaxed again when recrystallisation was complete. A theory of how the final crystal structure arises from the deformed matrix is proposed in which grain impingement during growth, when it involves orientation pinning, is followed by crystal aggregate spheroidisation to give the final polycrystalline structure. This means that a proportion of grains in a recrystallised aggregate have arisen from several separate nucleation events. The model, which is general, has implications for texture formation and can apply to both primary and secondary recrystallisation. It can also explain why the grain growth exponent is usually measured to be between 2 and 3. © 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.link_to_subscribed_fulltex
Simulation of VUV electroluminescence in micropattern gaseous detectors: the case of GEM and MHSP
Electroluminescence produced during avalanche development in gaseous
avalanche detectors is an useful information for triggering, calorimetry and
tracking in gaseous detectors. Noble gases present high electroluminescence
yields, emitting mainly in the VUV region. The photons can provide signal
readout if appropriate photosensors are used. Micropattern gaseous detectors
are good candidates for signal amplification in high background and/or low rate
experiments due to their high electroluminescence yields and radiopurity. In
this work, the VUV light responses of the Gas Electron Multiplier and of the
Micro-Hole Strip Plate, working with pure xenon, are simulated and studied in
detail using a new and versatile C++ toolkit. It is shown that the solid angle
subtended by a photosensor placed below the microstructures depends on the
operating conditions. The obtained absolute EL yields, determined for different
gas pressures and as functions of the applied voltage, are compared with those
determined experimentally.Comment: Accepted for publication in Journal of Instrumentatio
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