5,894 research outputs found
HYDROCRACKING OF FISCHER-TROPSCH PRODUCTS
The hydrocracking behavior the product of a Fischer-Tropsch synthesis consisting of a C4–C30 mixture of paraffins and olefins on a platinum/amorphous silica–alumina catalyst has been analyzed and optimized. The influence of temperature on the selectiveness of the hydrocracking has been investigated. Time and temperature optimization was performed in order to obtain the best operating conditions for the enhancement of gasoline and diesel cuts
“Chaves” para análise facial em Ortodontia
Poster apresentado nas XXIII Jornadas Internacionais de Medicina Dentária ISCSEM, 20-21 Março 2015, Egas Moniz, Caparica, Portugal
Methionine and Tryptophan Play Different Modulatory Roles in the European Seabass (Dicentrarchus labrax) Innate Immune Response and Apoptosis Signaling—An In Vitro Study
The range of metabolic pathways that are dependent on a proper supply of specific amino acids (AA) unveils their importance in the support of health. AA play central roles in key pathways vital for immune support and individual AA supplementation has shown to be able to modulate fish immunity. In vitro trials are important tools to evaluate the immunomodulatory role of AA, and the present study was conceived to evaluate methionine and tryptophan roles in immune-related mechanisms aiming to understand their effects in leucocyte functioning and AA pathways. For that purpose, head-kidney leucocytes were isolated and a primary cell culture established. The effect of methionine or tryptophan surplus on cell viability was assessed. Medium L-15 10% FBS without AA addition (0.5mM of L-methionine, 0.1 mM of L-tryptophan) was used as control. To that, L-methionine or L-tryptophan were supplemented at 1 and 2 times (M1x or M2x, and T1x or T2x). Nitric oxide, ATP, total antioxidant capacity, and immune-related genes were evaluated in response to lipopolysaccharides extracted from Photobacterium damselae subsp. piscicida or UV-inactivated bacteria). Moreover, caspase 3 activity and apoptosis-related genes were evaluated in response to the apoptosis-inducing protein, AIP56. Distinct roles in leucocytes’ immune response were observed, with contrasting outcomes in the modulation of individual pathways. Methionine surplus improved cell viability, polyamine production, and methionine-related genes expression in response to an inflammatory agent. Also, methionine supplementation lowered signals of apoptosis by AIP56, presenting lower caspase 3 activity and higher il1ß and nf-¿b expression. Cells cultured in tryptophan supplemented medium presented signals of an attenuated inflammatory response, with decreased ATP and enhanced expression of anti-inflammatory and catabolism-related genes in macrophages. In response to AIP56, leucocytes cultured in a tryptophan-rich medium presented lower resilience to the toxin, higher caspase 3 activity and expression of caspase 8, and lower expression of several genes, including nf-¿b and p65. This study showed the ability of methionine surplus to improve leucocytes’ response to an inflammatory agent and to lower signals of apoptosis by AIP56 induction, while tryptophan attenuated several cellular signals of the inflammatory response to UV-inactivated bacteria and lowered leucocyte resilience to AIP56.This work was partially supported by UIDB/04423/2020, UIDP/ 04423/2020 and INFLAMMAA (reference PTDC/CVT-CVT/ 32349/2017), financed by Portugal and the European Union through FEDER and COMPETE 2020, and national funds through Fundação para a Ciência e a Tecnologia (FCT, Portugal). MM and BC were supported by FCT, Portugal (SFRH/BD/108243/2015 and IF/00197/2015, respectively)
Normalization procedure for relaxation studies in NMR quantum information processing
NMR quantum information processing studies rely on the reconstruction of the
density matrix representing the so-called pseudo-pure states (PPS). An
initially pure part of a PPS state undergoes unitary and non-unitary
(relaxation) transformations during a computation process, causing a "loss of
purity" until the equilibrium is reached. Besides, upon relaxation, the nuclear
polarization varies in time, a fact which must be taken into account when
comparing density matrices at different instants. Attempting to use time-fixed
normalization procedures when relaxation is present, leads to various anomalies
on matrices populations. On this paper we propose a method which takes into
account the time-dependence of the normalization factor. From a generic form
for the deviation density matrix an expression for the relaxing initial pure
state is deduced. The method is exemplified with an experiment of relaxation of
the concurrence of a pseudo-entangled state, which exhibits the phenomenon of
sudden death, and the relaxation of the Wigner function of a pseudo-cat state.Comment: 9 pages, 5 figures, to appear in QI
Quantum state tomography and quantum logical operations in a three qubits NMR quadrupolar system
In this work, we present an implementation of quantum logic gates and
algorithms in a three effective qubits system, represented by a (I = 7/2) NMR
quadrupolar nuclei. To implement these protocols we have used the strong
modulating pulses (SMP). The various stages of each implementation were
verified by quantum state tomography (QST). It is presented here the results
for the computational base states, Toffolli logic gates, and Deutsch-Jozsa and
Grover algorithms. Also, we discuss the difficulties and advantages of
implementing such protocols using the SMP technique in quadrupolar systems.Comment: 24 pages, 8 figure
Rearranjos Subteloméricos: Apresentação de 21 Probandos, com Ênfase nos Casos Familiares
Intellectual disability affects 2% - 3% of the general population, with a chromosomal abnormality being found in 4% - 28% of these patients and a cryptic subtelomeric abnormality in 3% - 16%. In most cases, these subtelomeric rearrangements are submicroscopic, requiring techniques other than conventional karyotype for detection. They may be de novo or inherited from an affected parent or from a healthy carrier of a balanced chromosomal abnormality. The aim of this study was to characterize patients from our medical genetics center, in whom both a deletion and duplication in subtelomeric regions were found.Introdução:O défice intelectual afeta 2% – 3% da população geral, sendo encontrada uma alteração cromossómica em 4% – 28% dos casos e uma alteração subtelomérica em 3% – 16%. Estas alterações subteloméricas são, na maioria dos casos, submicroscópicas, não sendo detetadas no cariótipo convencional. Podem ser de novoou herdadas de um progenitor afetado ou de um progenitor saudável portador de um rearranjo equilibrado. O objetivo deste estudo foi caracterizar os doentes seguidos no nosso centro de genética médica com uma deleção e uma duplicação nas regiões subteloméricas.
Material e Métodos:Caracterização clínica e citogenética de 21 probandos com alterações subteloméricas seguidos no nosso centro entre 1998 e 2017.
Resultados:Foram caracterizados 21 probandos que apresentavam défice intelectual e dismorfia facial, pertencentes a 19 famílias. Sete tinham alterações do comportamento, cinco epilepsia e 14 outro sinal ou sintoma. Quatro tinham alterações no cariótipo e quatro foram diagnosticados por array-comparative genomic hybridization. Em quatro famílias não foi possível o estudo dos progenitores. Quando um dos fenótipos era dominante (síndrome de deleção ou duplicação), foi atribuída a classificação online mendelian inheritance in man.
Discussão:Foi realizada classificação dos doentes e das famílias. As alterações nas regiões subteloméricas são, apesar de raras, uma causa substancial para défice intelectual sindrómico com repercussões familiares importantes. É essencial lembrar que um arraycomparative genomic hybridizationnormal não exclui um rearranjo equilibrado familiar. Conclusão:O estudo dos progenitores é essencial não só para caracterização completa do rearranjo mas também para um aconselhamento genético preciso e identificação de familiares em risco de recorrência.
Palavras-chave:Deficiência Intelectual/genética; Rearranjo Génico/genética; Telómero/genéticainfo:eu-repo/semantics/publishedVersio
Writing electronic ferromagnetic states in a high-temperature paramagnetic nuclear spin system
In this paper we use the Nuclear Magnetic Resonance (NMR) to write eletronic
states of a ferromagnetic system into a high-temperature paramagnetic nuclear
spins. Through the control of phase and duration of radiofrequency pulses we
set the NMR density matrix populations, and apply the technique of quantum
state tomography to experimentally obtain the matrix elements of the system,
from which we calculate the temperature dependence of magnetization for
different magnetic fields. The effects of the variation of temperature and
magnetic field over the populations can be mapped in the angles of spins
rotations, carried out by the RF pulses. The experimental results are compared
to the Brillouin functions of ferromagnetic ordered systems in the mean field
approximation for two cases: the mean field is given by (i)
and (ii) , where is the external
magnetic field, and are mean field parameters. The
first case exhibits second order transition, whereas the second case has first
order transition with temperature hysteresis. The NMR simulations are in good
agreement with the magnetic predictions
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