245 research outputs found
Through the Looking-Glass: reflection of ant-diversity in ant-mimics
Trabalho final de mestrado integrado em Medicina, apresentado à Faculdade de Medicina da Universidade de Coimbra.Todos os anos nascem cerca de 15 milhões de crianças prematuras em todo o mundo e
mais de 1 milhão morre no primeiro mês devido a várias complicações.
A sobrevivência de um prematuro é cada vez maior devido aos avanços nos cuidados
perinatais, contudo estas crianças sofrem frequentemente de morbilidade respiratória crónica.
Os recém-nascidos prematuros têm um risco aumentado de possuírem alterações na função
pulmonar durante a infância, adolescência e idade adulta, bem como um risco aumentado de
infeções respiratórias, asma e doença pulmonar obstrutiva crónica. Estes problemas
respiratórios são particularmente evidentes quando estas crianças prematuras desenvolvem
displasia broncopulmonar.
O objetivo deste trabalho passa deste modo por destacar quais as principais
complicações a nível do sistema respiratório dos nascimentos pré-termo, salientando a
importância de um correto desenvolvimento do aparelho respiratório na fase pré-natal e pósnatal.An estimated 15 million of babies are born too early every year around the world and
over 1 million die in the first month due to various complications.
Recent advances in perinatal care have increased the survival rates of preterm birth
however, this improved survival has led to an increase in significant chronic respiratory
morbidity.
The children born preterm have an increased risk of abnormal lung function during
childhood, adolescence and adulthood, as well as respiratory infections, asthma and chronic
obstructive pulmonary disease. These respiratory problems are particularly evident when
these preterm birth develop bronchopulmonary dysplasia (BDP).
The purpose of this work is thus to highlight what are the main complications in the
respiratory system due to preterm birth emphasizing the importance of a correct development
of the respiratory system in prenatal and postnatal phase
Reprocessable Aliphatic Polydithiourethanes Based on the Reversible Addition Reaction of Diisothiocyanates and Dithiols
Aliphatic polydithiourethanes (PDTUs) were successfully synthesized from diisothiocyanates and dithiols having different values of the carbon atom number. The thermal properties and hydrogen-bonding behavior of PDTUs were studied in detail by using differential scanning calorimetry, thermal gravimetric analysis, temperature dependence nuclear magnetic resonance, Fourier transform infrared-attenuated total reflection, and density functional theory and semiempirical molecular orbital methods. In this work, we demonstrated that the thermal decomposition of PDTUs happened from the cleavage of the C–S bond of the dithiocarbamate moiety in the main chain and also that the active isothiocyanate and thiol groups were reprepared in the terminal of the decomposed polymer (i.e., oligomer). Furthermore, we found that the thermal depolymerization of PDTUs and the repolymerization of dithiourethane oligomers at room temperature proceeded repeatedly a few times
Synthesis and decrosslinking of networked polymers having zwitterion structure consisted by cyclic amidine and isothiocyanate
We have already found that the polymers, which are obtained by the polymerization of 4‐vinylphenyl isothoiocyanate after the zwitterion formation with cyclic amidines, are networked through the ionic interaction among the zwitterions becoming insoluble to various solvents. We report here on the results of the reaction of nucleophilic reagents such as amines and alcohols with the zwitterionic adduct to investigate about the decrosslinking through the resolution of ionic interactions. In the model reactions of amines and alcohols with the zwitterion compounds, which were consisted of the phenyl isothiocyanate and cyclic amidines, the reaction of nucleophilic reagents and zwitterionic adducts having methyl group at the 2‐position of the amidine proceed quantitatively. Based on the model reaction, such nucleophilic addition was applicable to decrosslinking reaction of the networked polymers containing the zwitterion structure in the side‐chain
Measuring the Beam Polarizations and the Luminosity at Photon-Photon Colliders
We present methods to measure the beam polarizations and the luminosity of
colliders at TeV energy scale.
The beam polarizations of a collider can easily be monitored
by comparing the numbers of events of the processes
and ,
where means or .
The luminosity of a collider is also measurable by the event
rate of boson pair productions and the light lepton pair productions.Comment: 16 pages and 7 figures attached as PostScript files, LaTeX, HUPD-9217
(Revised for 4 points: 2 are important, see the top of the file for details.
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