1,261 research outputs found
Directions in scenario planning literature - A review of the past decades
This paper provides a systematized overview of patterns in the scenario planning literature published in the last decades. Recently, scenario planning has enjoyed a revival, apparent in the 'boom' in published research on the matter. Consequently, a major issue that needs to be addressed is how to organize the literature along precise lines. A number of reviews that describe the current status of the body of literature and knowledge on scenario planning have made attempts to respond to such requirements. These studies agree that systematizing the existing literature is a necessary step in developing the field. This paper aims to contribute to this purpose. The review of the academic literature here conducted is thought to be useful for both academics and practitioners. For researchers, this systematic overview will be constructive not only in providing an analysis of the directions of published research but also in setting up a research agenda for the future. For managers and practitioners, it provides a clear outline of firm-related articles and discusses their contribution from a managerial point of view. It also raises awareness with regard to future analytical methods, and in particular, to scenario planning and its potential contribution to the competitiveness of firms. The research was carried out under the research Project Enterprise of the Future of the University of Aveiro. © 2009 Elsevier Ltd.Instituto de Investigação from University of Aveiro for the Project Enterprise of the Futur
Characterization of the virulence, growth temperature and antibiotic resistance of the Campylobacter jejuni IAL 2383 strain isolated from humans
The objective of this study was to characterize the C. jejuni IAL2383 strain isolated from humans in Brazil. Transcripts for the racR, dnaJ and ciaB genes were found and flaA, plda and cadF genes were present in the genome and bacteria was sensitive to most of the important antimicrobials used to treat humans. C. jejuni IAL2383 is a good experimental model to analyze the interactions with cells
Developing accident frequency prediction models for urban roads: A case study in São Paulo, Brazil
The growing number of vehicles and the evolving behaviour of road users present new and additional challenges to road safety. Study on the variables that influence the frequency of crash occurrences such as road geometry, junction, speed and land use are needed as they have proven effects on the number and severity of crashes. In this paper, we identify and assess the variables, namely road geometry, vehicle speed, traffic volume, land use and junction type, and develop accident frequency prediction models for a main urban transport corridor in São Paulo, Brazil. Crash data was provided by the traffic management company of the city, other datasets were obtained from a mix of primary and secondary sources including roadside cameras, Geographic Information Systems (GIS) and digital mapping tools. The studied road was segmented and the coefficients associated with variables in the segments were obtained using Poisson regression through a stepwise variable selection procedure. Two models with junctions density per type (access/km, T-junction unsignalised/km, T-junction signalised/km and crossroads/km) and junction density per merged type (signalised/km and unsignalised/km) along with land use per type (commercial and residential) are developed. The junction density and land use are found to be significant and positively correlated with crash frequency. The models were evaluated by statistical means for their accuracy of predicting the crashes, and validated with additional information obtained from field observation
Momentum distribution of a trapped Fermi gas with large scattering length
Using a scattering length parametrization of the BCS-BEC crossover as well as
the local density approximation for the density profile, we calculate the
momentum distribution of a harmonically trapped atomic Fermi gas at zero
temperature. Various interaction regimes are considered, including the BCS
phase, the unitarity limit and the molecular regime. We show that the relevant
parameter which characterizes the crossover is given by the dimensionless
combination , where is the number of atoms, is the
scattering length and is the oscillator length. The width of the
momentum distribution is shown to depend in a crucial way on the value and sign
of this parameter. Our predictions can be relevant for experiments on ultracold
atomic Fermi gases near a Feshbach resonance.Comment: 6 pages, 2 figures. Submitted to Phys. Rev. A. Added reference
Pairing in spin polarized two-species fermionic mixtures with mass asymmetry
We discuss on the pairing mechanism of fermions with mismatch in their fermi
momenta due to a mass asymmetry. Using a variational ansatz for the ground
state we also discuss the BCS -BEC crossover of this system. It is shown that
the breached pairing solution with a single fermi surface is stable in the BEC
regime. We also include the temperatures effect on the fermion pairing within
an approximation that is valid for temperatures much below the critical
temperature.Comment: 8 pages and 6 figures, few typos corrected, version to appear in EPJ
Morphology of Gambierdiscus excentricus (Dinophyceae) with emphasis on sulcal plates
Gambierdiscus excentricus is an epibenthic dinoflagellate able to produce ciguatoxin and maitotoxin-like
compounds that are responsible for ciguatera fish poisoning. Morphological descriptions and molecular characterization
of two G. excentricus strains isolated from Brazil and maintained in culture were provided. The most complete description
of the morphology of the sulcal region of Gambierdiscus based on light and scanning electron microscopy was presented.
The sulcal area morphology and nomenclature used by different authors to name the sulcal plates in Gambierdiscus were
reviewed. Two small sulcal plates (S.m.a. and S.m.p.) were shown for the first time. Phylogenetic trees based on D1–D3
and D8–D10 large subunits of ribosomal RNA gene sequences showed that the strains of G. excentricus from Brazil
clustered with strains of G. excentricus isolated from its type locality, the Canary Islands. Both phylogenetic trees
reconstructed the same relationships among all the formally described Gambierdiscus species and Gambierdiscus sp.
ribotype 2 and Gambierdiscus sp. type 2.Versión del editor2,080
O papel da atenção primária à saúde no enfrentamento de IST
A atenção Primária à Saúde é considerada a porta de entrada preferencial do usuário no Sistema Único de Saúde (SUS). A partir dela é possível garantir, entre outros, o diagnóstico e tratamento precoces de doenças como as infecções sexualmente transmissíveis (IST), hepatite B e C, HIV e sífilis. Descrever a experiência de uma ação realizada com usuários em uma Unidade Básica de Saúde (UBS) sobre IST, com o intuito de melhorar a adesão da população ao cuidado com IST e minimizar seus riscos. Trata-se de um estudo descritivo do tipo relato de experiência, desenvolvido durante as atividades práticas dos estudantes da graduação de medicina na UBS de Jardim Brasil V, Olinda-PE, em setembro de 2020. Estiveram envolvidos 20 usuários da UBS de demanda espontânea, após divulgação prévia a esta ação, considerando os cuidados em tempos de pandemia. Foi realizada uma triagem com testes rápidos para sífilis, HIV, hepatite B e C, além de receberem informações sobre IST e da importância da investigação precoce. A maioria dos participantes foram do sexo feminino, 15% testaram positivo (sífilis). Nenhum deles tinham realizado estes testes antes. Apenas 15% dos voluntários tinham conhecimento dos testes de triagem das IST e compreendiam a importância desta realização. O atendimento imediato de uma pessoa com IST não é apenas uma ação curativa, mas também visa à interrupção da cadeia de transmissão, à prevenção de outras IST e complicações decorrentes destas infecções
Stripes, Pseudogaps, and Van Hove Nesting in the Three-band tJ Model
Slave boson calculations have been carried out in the three-band tJ model for
the high-T_c cuprates, with the inclusion of coupling to oxygen breathing mode
phonons. Phonon-induced Van Hove nesting leads to a phase separation between a
hole-doped domain and a (magnetic) domain near half filling, with long-range
Coulomb forces limiting the separation to a nanoscopic scale. Strong
correlation effects pin the Fermi level close to, but not precisely at the Van
Hove singularity (VHS), which can enhance the tendency to phase separation. The
resulting dispersions have been calculated, both in the uniform phases and in
the phase separated regime. In the latter case, distinctly different
dispersions are found for large, random domains and for regular (static)
striped arrays, and a hypothetical form is presented for dynamic striped
arrays. The doping dependence of the latter is found to provide an excellent
description of photoemission and thermodynamic experiments on pseudogap
formation in underdoped cuprates. In particular, the multiplicity of observed
gaps is explained as a combination of flux phase plus charge density wave (CDW)
gaps along with a superconducting gap. The largest gap is associated with VHS
nesting. The apparent smooth evolution of this gap with doping masks a
crossover from CDW-like effects near optimal doping to magnetic effects (flux
phase) near half filling. A crossover from large Fermi surface to hole pockets
with increased underdoping is found. In the weakly overdoped regime, the CDW
undergoes a quantum phase transition (), which could be obscured
by phase separation.Comment: 15 pages, Latex, 18 PS figures Corrects a sign error: major changes,
esp. in Sect. 3, Figs 1-4,6 replace
Soil penetration resistance analysis by multivariate and geostatistical methods
The penetration resistance (PR) is a soil attribute that allows identifies areas with restrictions due to compaction, which results in mechanical impedance for root growth and reduced crop yield. The aim of this study was to characterize the PR of an agricultural soil by geostatistical and multivariate analysis. Sampling was done randomly in 90 points up to 0.60 m depth. It was determined spatial distribution models of PR, and defined areas with mechanical impedance for roots growth. The PR showed a random distribution to 0.55 and 0.60 m depth. PR in other depths analyzed showed spatial dependence, with adjustments to exponential and spherical models. The cluster analysis that considered sampling points allowed establishing areas with compaction problem identified in the maps by kriging interpolation. The analysis with main components identified three soil layers, where the middle layer showed the highest values of PR.La resistencia a la penetración (RP) es un atributo del suelo que permite identificar zonas con restricciones debido a la compactación, que se traduce en impedancia mecánica para el desarrollo de las raíces y en una menor productividad de los cultivos. El objetivo del presente trabajo fue caracterizar la RP de un suelo agrícola, mediante análisis geoestadístico y multivariado. El muestreo se realizó de manera aleatoria en 90 puntos, hasta una profundidad de 0,60 m. Se determinaron los modelos de distribución espacial de la RP y se delimitaron áreas con problemas de impedancia mecánica de las raíces. La RP presentó distribución aleatoria a 0,55 y 0,60 m de profundidad. La RP en las otras profundidades analizadas mostraron dependencia espacial, con ajustes a modelos exponenciales y esféricos. El análisis jerárquico que consideró puntos de muestreo, permitió establecer zonas con problemas de compactación, identificadas en los mapas obtenidos mediante interpolación por kriging. El análisis de componentes principales permitió identificar tres capas de suelo, donde la capa intermedia fue la que presentó los mayores valores de RP
Histological evaluation of the liver of mice with sarcoma-180 treated with salazinic acid
Abstract Many of the drugs used to fight cancer cells induce various damage causing hepatotoxic effects which are characterized by tissue changes. The aim of the study is to know the possible effects of salazinic acid on livers of mice exposed to Sacoma-180. The tumor was grown in the animals in ascitic form and inoculated subcutaneously in the axillary region of the mouse developing the solid tumor. Treatment with salazinic acid (25 and 50 mg/kg) and 5-Fluorouracil (20 mg/kg) started 24-hours after inoculation and was performed for 7 days. To verify these effects, the qualitative method of histological criteria investigated in liver tissue was used. It was observed that all treated groups showed an increase of pyknotic nuclei in relation to the negative control. There was an increase in steatosis in all groups compared to the negative control but there was a decrease in the groups treated with salazinic acid in the 5-Fluorouracil. There was no necrosis in the salazinic acid treated groups. However, this effect was seen in 20% of the positive control group. Therefore, it can be concluded that salazinic acid did not show hepatoprotective action on mice but demonstrated a decrease in steatosis and absence of tissue necrosis
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