993 research outputs found
Sustainable cycle-tourism for society: Integrating multi-criteria decision-making and land use approaches for route selection
Cycle tourism is a sustainable active vacation, which is quickly growing in recent years. Although it has several benefits for society and users (e.g., social connections, amusement, and physical and mental health), cycle tourism requires an adequate route network to enjoy destinations with historical and landscape peculiarities. Past literature mainly investigated motivations and preferences for cycle tourists and proposed optimisation methods in planning routes. However, applying assessment methods for prioritising cycle-tourist routes is a seldom-explored topic. This study aims to address this gap by applying an integrated method for evaluating and prioritising cycle routes, searching for a compromise between route characteristics, service provided to users, and natural and building contexts crossed. It jointly includes Multi-Criteria Decision Methods (MCDMs) and a land use approach: AHP determines the weights of criteria and parameters describing cycle routes; GIS elaborates spatial analysis of parameters; ELECTRE I and VIKOR help find a compromise solution amongst different cycle routes. The integrated method involved a panel of experts to collect data, and it is applied to the wide-study area of Franciacorta (Italy). Some comparisons with other MCDMs are made to justify the results. The findings could support multi-institutions prioritising cycle route alternatives in deciding their building
Monte-Carlo simulations of the recombination dynamics in porous silicon
A simple lattice model describing the recombination dynamics in visible light
emitting porous Silicon is presented. In the model, each occupied lattice site
represents a Si crystal of nanometer size. The disordered structure of porous
Silicon is modeled by modified random percolation networks in two and three
dimensions. Both correlated (excitons) and uncorrelated electron-hole pairs
have been studied. Radiative and non-radiative processes as well as hopping
between nearest neighbor occupied sites are taken into account. By means of
extensive Monte-Carlo simulations, we show that the recombination dynamics in
porous Silicon is due to a dispersive diffusion of excitons in a disordered
arrangement of interconnected Si quantum dots. The simulated luminescence decay
for the excitons shows a stretched exponential lineshape while for uncorrelated
electron-hole pairs a power law decay is suggested. Our results successfully
account for the recombination dynamics recently observed in the experiments.
The present model is a prototype for a larger class of models describing
diffusion of particles in a complex disordered system.Comment: 33 pages, RevTeX, 19 figures available on request to
[email protected]
Dynamical Characterization of Galaxies at z~4-6 via Tilted Ring Fitting to ALMA [CII] Observations
Until recently, determining the rotational properties of galaxies in the
early universe (z>4, Universe age <1.5Gyr) was impractical, with the exception
of a few strongly lensed systems. Combining the high resolution and sensitivity
of ALMA at (sub-) millimeter wavelengths with the typically high strength of
the [CII] 158um emission line from galaxies and long-developed dynamical
modeling tools raises the possibility of characterizing the gas dynamics in
both extreme starburst galaxies and normal star forming disk galaxies at z~4-7.
Using a procedure centered around GIPSY's ROTCUR task, we have fit tilted ring
models to some of the best available ALMA [CII] data of a small set of
galaxies: the MS galaxies HZ9 & HZ10, the Damped Lyman-alpha Absorber (DLA)
host galaxy ALMA J0817+1351, the submm galaxies AzTEC/C159 and COSMOS
J1000+0234, and the quasar host galaxy ULAS J1319+0950. This procedure directly
derives rotation curves and dynamical masses as functions of radius for each
object. In one case, we present evidence for a dark matter halo of O(10^11)
solar masses. We present an analysis of the possible velocity dispersions of
AzTEC/C159 and ULAS J1319+0950 based on matching simulated observations to the
integrated [CII] line profiles. Finally, we test the effects of observation
resolution and sensitivity on our results. While the conclusions remain limited
at the resolution and signal-to-noise ratios of these observations, the results
demonstrate the viability of the modeling tools at high redshift, and the
exciting potential for detailed dynamical analysis of the earliest galaxies, as
ALMA achieves full observational capabilities.Comment: 20 pages, 6 figures, Accepted for publication in Ap
Use of Foley catheter in control of internal carotid hemorrhage during endoscopic endonasal surgery
Internal carotid artery (ICA) injuries during endoscopic endonasal surgery (EES) are rare life-threatening events. We describe a technique to manage ICA injuries based on the use of Foley catheters.A 26-year-old female underwent endoscopic transnasal trans-sphenoidal removal of pituitary adenoma. Cerebrospinal fluid leak occurred 4 days postoperatively. During repair procedure, accidental injury of ICA occurred. Emergency nasal packing through positioning of four Foley urologic catheters was successfully performed to stop bleeding. The patient did not report neurologic deficits.In author's opinion, Foley catheters are suitable to obtain immediate bleeding control since they are rapidly available and easily usable
Multiparametric Porous Silicon Sensors
We investigated the possibility of using several sensing parameters from porous silicon in order to improve gas selectivity. By fabricating porous silicon optical microcavities, three independent quantities can be measured, i.e. the electrical conductance, the photoluminescence intensity, and the wavelength of the optical resonance. We monitored the change of these three parameters as a function of NO2 (0.5-5 ppm), ethanol (300-15000 ppm) and relative humidity (0-100%). Preliminary results confirm that the examined species affect the parameters in a different way, both as a relative change and as dynamic
A comparative cycling path selection for sustainable tourism in Franciacorta. An integrated AHP-ELECTRE method
Cycle tourism is a form of sustainable itinerant tourism expanding in Italy and the rest of the world, with prospects for growth in coming years. Europe and North America have already developed a wide range of cycling infrastructures tied to tourism experiences. Benefits induced are generally recognised: first, it is a sustainable solution that increases local economics while conserving the environment; second, it guarantees advantages on social connections, amusement, and physical and mental health. However, it requires an adequate network to enjoy destinations as historical and landscape peculiarities. Currently, literature provides some methods for planning itineraries dedicated to cycle tourism. Despite that, there is less attention on how evaluating existing or already planned tourist itineraries. This study covers this gap, by applying an integrated method to assess bicycle connections for tourism experiences within municipalities. Since this evaluation may contain many conflicting criteria (e.g., preferences of public administrator, technical and economic viability) and possible alternatives, this study frames the method as a multi-criteria decision-making problem (MCDM). Specifically, at first, the Analytical Hierarchy Process (AHP) is adopted to calculate weights for each criterium; next, the ELimination Et Choix Traduisant la REalitè (ELECTRE) method is applied to provide a (possible) priority ranking of cycling tourist paths among alternatives, by computing indices of discordance and concordance between pairs of alternatives. The framework is applied to the Franciacorta area (North-East Italy), a national and international tourist relevance territory encompassing 22 municipalities. This study may be useful for public administrators to rationalise and prioritise cycling routes
The Escherichia coli RutR transcription factor binds at targets within genes as well as intergenic regions.
The Escherichia coli RutR protein is the master regulator of genes involved in pyrimidine catabolism. Here we have used chromatin immunoprecipitation in combination with DNA microarrays to measure the binding of RutR across the chromosome of exponentially growing E. coli cells. Twenty RutR-binding targets were identified and analysis of these targets generated a DNA consensus logo for RutR binding. Complementary in vitro binding assays showed high-affinity RutR binding to 16 of the 20 targets, with the four low-affinity RutR targets lacking predicted key binding determinants. Surprisingly, most of the DNA targets for RutR are located within coding segments of the genome and appear to have little or no effect on transcript levels in the conditions tested. This contrasts sharply with other E. coli transcription factors whose binding sites are primarily located in intergenic regions. We suggest that either RutR has yet undiscovered function or that evolution has been slow to eliminate non-functional DNA sites for RutR because they do not have an adverse effect on cell fitness
Bisphosphonate-associated jaws osteonecrosis: an important complication of oncology treatment
Os bisfosfonatos são um grupo de medicamentos utilizados no tratamento de doenças malignas metastáticas e em outras doenças ósseas como osteoporose e doença de Paget. A despeito dos seus benefÃcios, uma importante complicação denominada de osteonecrose dos maxilares vem sendo observada nos pacientes usuários crônicos dos bisfosfonatos que se caracteriza clinicamente por exposições ósseas na região maxilofacial persistente, acompanhadas de osteomielite, geralmente sintomáticas e cujo tratamento é complexo. Este estudo tem por objetivo revisar a literatura sobre a osteonecrose associada ao uso dos bisfosfonatos, em especial, em oncologia, no perÃodo de 2003 a 2008. Serão apresentados e discutidos os fatores de risco, aspectos etiopatogênicos, clÃnicos, imagenológicos, terapêuticos e preventivos desta doença. Devido à dificuldade de tratamento da osteonecrose associada aos bisfosfonatos, o foco deve ser a prevenção, sendo o ideal a eliminação de quadros infecciosos orais antes da terapia com os bisfosfonatos ter sido iniciada e minimizar traumas em boca após o uso destes medicamentos.Bisphosphonates are drugs used in the treatment of malignant metastatic diseases and in other bone lesions such as osteoporosis and Paget´s disease. Besides their benefits, jaw osteonecrosis, an important side effect, has been observed in long-term users of these drugs. Jaw osteonecrosis is clinically characterized by prolonged maxillary and mandible bone exposure accompanied by osteomyelitis. These lesions are usually symptomatic and difficult to treat. This study has the objective of reviewing publications from 2003 to 2008 about bisphosphonate-associated jaw osteonecrosis, in particular in relation to oncology. Risk factors, and etiopathological, clinical, radiographic, therapeutic, and preventive aspects of this condition are presented and discussed. Due to the difficulty to treat this disease, the focus must be prevention, with the ideal therapy being the elimination of oral infections before treatment with bisphosphonates is initiated thereby attempting to minimize possible traumas to the mouth with the use of these medications
ALMA suggests outflows in z ~ 5.5 galaxies
We present the first attempt to detect outflows from galaxies approaching the
Epoch of Reionization (EoR) using a sample of 9 star-forming () galaxies for which the [CII]158m line
has been previously obtained with ALMA. We first fit each line with a Gaussian
function and compute the residuals by subtracting the best fitting model from
the data. We combine the residuals of all sample galaxies and find that the
total signal is characterised by a flux excess of mJy extended over
km~s. Although we cannot exclude that part of this signal is
due to emission from faint satellite galaxies, we show that the most probable
explanation for the detected flux excess is the presence of broad wings in the
[CII] lines, signatures of starburst-driven outflows. We infer an average
outflow rate of , providing a loading
factor in agreement with observed local
starbursts. Our interpretation is consistent with outcomes from zoomed
hydro-simulations of {\it Dahlia}, a galaxy () whose feedback-regulated star formation results into an
outflow rate . The quality of the ALMA
data is not sufficient for a detailed analysis of the [CII] line profile in
individual galaxies. Nevertheless, our results suggest that starburst-driven
outflows are in place in the EoR and provide useful indications for future ALMA
campaigns. Deeper observations of the [CII] line in this sample are required to
better characterise feedback at high- and to understand the role of outflows
in shaping early galaxy formation
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