9,166 research outputs found
Seed bank and control of Rottboellia exaltata using clomazone alone and in combination with other herbicides.
Objetivou-se, com este trabalho, estudar o banco de sementes e o controle de Rottboellia exaltata L.f. com clomazone, isolado e em associação com outros herbicidas, em áreas de cana-soca com baixa e alta infestação.bitstream/item/131076/1/4466-18529-1-PB-Nubia.pdfOn line
Structural and optical properties of Zn0.9 Mn0.1 O/ZnO core-shell nanowires designed by pulsed laser deposition
Partilhar documento na coleção da comunidade Laboratório Associado I3NCore-shell ZnO/ZnMnO nanowires on a-Al2O3 and GaN (buffer layer)/Si (111) substrates were fabricated by pulsed laser deposition using a Au catalyst. Two ZnO targets with a Mn content of 10% were sintered at 1150 and 550 °C in order to achieve the domination in them of paramagnetic MnO2 and ferromagnetic Mn2O3 phases, respectively. Cluster mechanism of laser ablation as a source of possible incorporation of secondary phases to the wire shell is discussed. Raman spectroscopy under excitation by an Ar+ laser revealed a broad peak related to the Mn-induced disorder and a redshift in the A1-LO phonon. Resonant Raman measurements revealed an increase in the multiphonon scattering caused by disorder in ZnO upon doping by Mn. Besides the UV emission, a vibronic green emission band assisted by a ∼ 71 meV LO phonon is also observed in the photoluminescence spectra. Core-shell structures with smooth shells show a high exciton to green band intensity ratio ( ∼ 10) even at room temperature.
© 2009 American Institute of PhysicsSANDiE Network of Excellence of the EUFCT-PTDC/FIS/72843/200
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ISO observations of M8, the Lagoon nebula
In this paper, IRAS, ISO, and molecular line observations of the M8 and M8E sources in the Lagoon Nebula are reported
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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
Subject age in P300 BCI
This paper presents a study about the amplitude, latency and distribution of P300 in twelve healthy volunteers (5 women and 7 men, aged between 19-70, with a mean of 35.5 years) that were submitted to two Novelty Oddball Paradigms. The difference between them is on stimulus modalities, which are visual and auditory. Usually, a P300-based brain computer interface has visual stimuli but we are also interested in making analogies between the two modalities. In both test modalities were presented 3 types of stimuli: a ‘standard’ stimulus, a ‘target’ stimulus, to which the subject must respond, and a ‘novel’ stimulus. Most of the subjects were students and are naive to the purposes of the experiment. The subject is not warned about the ‘novel’. We recorded scalp potentials from 18 channels
distributed in a standard configuration 10-20 system. Target P300 had more relevance than novel P300 for a BCI application.
Results show relevant differences in amplitude and latency in P300 signal for different ages. The Older subjects (>51 years) show smaller P300 amplitudes than younger. Therefore, the subject age must be taken into account when a P300 BCI application is implemented.Fundação para a Ciência e Tecnologia (FCT
The effects of grazing management in montado fragmentation and heterogeneity
The Portuguese silvo-pastoral system montado is broadly classified as a High Nature Value (HNV) system since it corresponds to farmland hosting high biodiversity levels, and such biodiversity depends on specific land use practices. However, in recent decades a decline both in the totalmontado area and in the tree cover density within the montado has been observed, driven mainly by management changes. This decline may result in biodiversity loss. Grazing is a central aspect determining the long-term sustainability of the montado system and it has implications also on themontado structural diversity, particularly on connectivity and heterogeneity, which is crucial for the maintenance of montado HNV. The aim of this paper is to demonstrate how variations in montadostructural diversity are correlated with grazing management and its implications on the value of the system for conservation. The empirical data derives from a case study composed of 41 montadofarms in two municipalities of the Alentejo region. Data on grazing management, biophysical and spatial factors were collected and several metrics were calculated to assess montado fragmentation and heterogeneity. A multivariate analysis was performed using generalized additive models. Results show that different grazing patterns, depending on stocking density and grazing animal type, are correlated with variations in montado fragmentation and heterogeneity. Particularly, cattle’s grazing is shown to have adverse effects on the montado fragmentation, while sheep grazing is shown to have stronger impacts on the heterogeneity within the montado patches
Design and analysis of a 6 GHz chip antenna on glass substrates for integration with RF/wireless microsystems
We report on design and characterization of chip-size antennas for operation at 6 GHz
and use in wireless microsystems. Use of a glass substrate and application of wafer-level chipscale packaging (WLCSP) techniques like adhesive wafer bonding and through-wafer electrical via formation, combined with the selected antenna type allows on-chip integration and is the main
issue of our work. A short-range wireless link between two systems both equipped with a 11.7x12.4 mm2 patch antenna (measured characteristics: 6 GHz central frequency, 100 MHz bandwidth @ -10 dB, 3 dB gain, 51% efficiency) realized on a Corning Pyrex #7740 glass substrate is demonstrated.Fundação para a Ciência e Tecnologia (FCT), project (SFRH/BD/4717/2001 and POCTI/ESE/38468/2001
Design and tolerance analysis of a 5.7 GHz chip-size microstrip antenna on high resistivity silicon
This paper reports the FEM model, design, fabrication and characterization of a square patch antenna built on high-resistivity silicon (HRS) for operation at 5.7 GHz.Fundação para a Ciência e Tecnologia (FCT
The influence of overweight and obesity in the oral health of a sample of Portuguese adults
Background: Overweight and obesity may lead to different problems in various body systems and in the oral cavity. Dental caries and periodontal disease have been related with overweight. The aim of this study was to assess how overweight and obesity have impact on the lifestyle, oral habits and oral pathologies. Methods: We conducted an observational cross-sectional study where we applied a questionnaire to 140 individuals from Lisbon and Viseu, Portugal., which 70 had a normal Body Mass Index (BMI) (control group) and 70 had an excessive BMI. We also made an oral observation in each individual to record the permanent teeth decayed, missing and filled index (DMFT), the Community Periodontal Index and the oral hygiene status. Results: From the final sample, 30% of the subjects with overweight brushed their teeth once a day or less, while the majority (62.9%) of the control group brushed twice a day. In the oral examination, 70% had calculus, while in the control group only 22.5% presented calcified plaque. The DMFT was higher among the obesity group in comparison with the control group. Regarding periodontal disease, the participants with overweight need more dental intervention (81.4%) in contrast with the control group (14%). Conclusions: Most overweight and obese individuals present precarious oral hygiene habits, higher prevalence of dental caries, and worse periods of periodontal health. They are not aware of the repercussions of the association between their cariogenic diet, oral health and overweight.info:eu-repo/semantics/publishedVersio
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