896 research outputs found
Evolution of body mass índex of women undergoing bariatric surgery in the pre- and pos-operative period: a retrospective study
[resumo][abstract
Potential for macro and micronutrients extraction from tomato plants with different soil water stresses
Different tomato cultivars may present differentiated water needs, making it
indispensable to study water demand. Thus, the objective of this work was to evaluate the
influence of six water stresses in the soil on the extraction potential of macro and micronutrients
in the aerial part of tomato in vegetative stage, cultivar ‘Dominador’ F1, under protected
cultivation and drip. The experiment was installed in a greenhouse with a randomized block
design with four replications. The treatments consisted of six soil water stresses as indicative of
the time of irrigation. The preset stresses were 20, 45, 70, 95, 120 and 145 kPa at 20 cm depth.
At 140 days after transplanting, the variables evaluated were: the macro and micronutrient content
of shoots. The results showed that to obtain higher levels of macro (P and S) and micronutrients
(B and Cu) of the total aerial part of the ‘Dominador’ tomato plant F1, it was obtained at a voltage
of 20 kPa, and its value was reduced linearly with the increase of the water tension in the soil
Foreword: Control and Conservation of Lampreys Beyond 2020 – Proceedings from the 3rd Sea Lamprey International Symposium (SLIS III)
This special issue summarizes outcomes from the 3rd Sea Lamprey International Symposium (SLIS III; Fig. 1) held 28 July – 2 August 2019 at Wayne State University in Detroit, Michigan, U.S.A. The first two symposia (SLIS I and SLIS II) were held 30 July – 8 August 1979 at Northern Michigan University in Marquette, Michigan and 14–18 August 2000 at Lake Superior State University in Sault Ste. Marie, Michigan, respectively. The published volumes from these symposia in 1980 (Canadian Journal of Fisheries and Aquatic Sciences, Volume 37, Issue 11) and 2003 (Journal of Great Lakes Research Volume 29, Supplement 1) have been invaluable references for the broader scientific community and for management agencies around the Laurentian Great Lakes; cited over 4800 and 3300 times, respectively. SLIS III was attended by over 150 scientists, biologists, resource managers, graduate students, and Commission advisors, including participants from Australia, Canada, China, Japan, New Zealand, Portugal, Spain, the United Kingdom, and the United States (Fig. 2). Similar to SLIS I and SLIS II, the goals of SLIS III were to provide a forum to (i) update and publish information on sea lamprey control and research on lampreys since SLIS II, (ii) exchange knowledge and ideas to bring practitioners to a common plateau of understanding, and (iii) develop innovative initiatives and stimulate new vigor in efforts to control sea lamprey in the Great Lakes and to conserve lampreys in their native ranges. The emphasis on conservation of lampreys is unique to SLIS III and reflects a heightened international recognition that scientific and management advances supporting sea lamprey control in the Great Lakes can benefit the global effort to conserve native lampreys and vice versa
Thermodynamic Properties of the One-Dimensional Extended Quantum Compass Model in the Presence of a Transverse Field
The presence of a quantum critical point can significantly affect the
thermodynamic properties of a material at finite temperatures. This is
reflected, e.g., in the entropy landscape S(T; c) in the vicinity of a quantum
critical point, yielding particularly strong variations for varying the tuning
parameter c such as magnetic field. In this work we have studied the
thermodynamic properties of the quantum compass model in the presence of a
transverse field. The specific heat, entropy and cooling rate under an
adiabatic demagnetization process have been calculated. During an adiabatic
(de)magnetization process temperature drops in the vicinity of a field-induced
zero-temperature quantum phase transitions. However close to field-induced
quantum phase transitions we observe a large magnetocaloric effect
A Green's function approach to transmission of massless Dirac fermions in graphene through an array of random scatterers
We consider the transmission of massless Dirac fermions through an array of
short range scatterers which are modeled as randomly positioned -
function like potentials along the x-axis. We particularly discuss the
interplay between disorder-induced localization that is the hallmark of a
non-relativistic system and two important properties of such massless Dirac
fermions, namely, complete transmission at normal incidence and periodic
dependence of transmission coefficient on the strength of the barrier that
leads to a periodic resonant transmission. This leads to two different types of
conductance behavior as a function of the system size at the resonant and the
off-resonance strengths of the delta function potential. We explain this
behavior of the conductance in terms of the transmission through a pair of such
barriers using a Green's function based approach. The method helps to
understand such disordered transport in terms of well known optical phenomena
such as Fabry Perot resonances.Comment: 22 double spaced single column pages. 15 .eps figure
School dropout, problem behaviour and poor academic achievement : a longitudinal view of portuguese male offenders
This study examines school drop outs from the perspective of male adults
themselves through interviews with offenders currently serving sentences. Participants
were 10 Portuguese male inmates, between the ages of 19 and 46 years of age,
incarcerated in two prison facilities of the Azores. Qualitative and interpretative methods
were carried out using a semi-structured in-depth individual interview that was audiorecorded
and conducted on the basis of a list of topics. Interview transcripts and thematic
analysis were used in data treatment and analysis. The findings primarily indicate that
poor academic achievement and emotional and behavioural difficulties of participants
played a particular role in early school drop out. The trajectories these individuals
followed within the education system presented problem behaviour, learning disabilities,
and/or foster care interventions. While school drop out circumstances were apparently
various, analysis showed that they were underpinned by three distinct sets of conditions
generally not addressed by the education system. The analysis of the triggering factors
and the maintenance dynamics of school drop outs indicated three distinct types:
retention/absenteeism, life turning points and positive resolution. Implications for
secondary prevention and screening practices are discussed.FCT (SFRH/ BD/ 44245/ 2008)CIEC - unidade de investigação 317 da FC
Simulation of dimensionality effects in thermal transport
The discovery of nanostructures and the development of growth and fabrication
techniques of one- and two-dimensional materials provide the possibility to
probe experimentally heat transport in low-dimensional systems. Nevertheless
measuring the thermal conductivity of these systems is extremely challenging
and subject to large uncertainties, thus hindering the chance for a direct
comparison between experiments and statistical physics models. Atomistic
simulations of realistic nanostructures provide the ideal bridge between
abstract models and experiments. After briefly introducing the state of the art
of heat transport measurement in nanostructures, and numerical techniques to
simulate realistic systems at atomistic level, we review the contribution of
lattice dynamics and molecular dynamics simulation to understanding nanoscale
thermal transport in systems with reduced dimensionality. We focus on the
effect of dimensionality in determining the phononic properties of carbon and
semiconducting nanostructures, specifically considering the cases of carbon
nanotubes, graphene and of silicon nanowires and ultra-thin membranes,
underlying analogies and differences with abstract lattice models.Comment: 30 pages, 21 figures. Review paper, to appear in the Springer Lecture
Notes in Physics volume "Thermal transport in low dimensions: from
statistical physics to nanoscale heat transfer" (S. Lepri ed.
β -decay half-lives of neutron-rich nuclides in the A=100-110 mass region
β-decay half-lives of neutron-rich nuclides in the A=100-110 mass region have been measured using an implantation station installed inside of the Summing NaI(Tl) (SuN) detector at the National Superconducting Cyclotron Laboratory. Accurate half-lives for these nuclides are important for nuclear astrophysics, nuclear structure, and nuclear technology. The half-lives from the present work are compared with previous measurements, showing overall good agreement
Tensor Correlations Measured in 3He(e,e'pp)n
We have measured the 3He(e,e'pp)n reaction at an incident energy of 4.7 GeV
over a wide kinematic range. We identified spectator correlated pp and pn
nucleon pairs using kinematic cuts and measured their relative and total
momentum distributions. This is the first measurement of the ratio of pp to pn
pairs as a function of pair total momentum, . For pair relative
momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low and
rises to approximately 0.5 at large . This shows the dominance of
tensor over central correlations at this relative momentum.Comment: 4 pages, 4 figures, submitted to PR
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