Isabel Cristina Giehl

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Growth of cells in 3-D porous scaffolds has gained importance in the field of tissue engineering. The scaffolds guide cellular growth, synthesize extracellular matrix and other biological molecules, and make the formation of tissues and functional organs easier. The aim of this study is to use α-tricalcium phosphate cement in order to obtain new types of(More)
The production rates of D + c / ¯ Λ − c in Z → c¯ c decays are measured using the LEP I data sample recorded by the ALEPH detector. The fractional energy spectrum of the D * ± is well described as the sum of three contributions: charm hadronisation, b hadron decays and gluon splitting into a pair of heavy quarks. The probability for a c quark to hadronise(More)
Extensive searches for evidence of compositeness of quarks and leptons have been made using the full set of ALEPH data from LEP running at the Z peak. They include searches for radiative and weak decays of excited leptons, and radiative and gluonic decays of excited quarks, produced either singly or in pairs. Searches have also been made for a scalar(More)
Searches for the production of supersymmetric particles under the assumption that R-parity is violated via a single dominant LL ¯ E, LQ ¯ D or ¯ U ¯ D ¯ D coupling were performed. These use the data collected by the ALEPH detector at LEP at centre-of-mass energies from 188.6 to 201.6 GeV. The numbers of candidate events observed in the data are consistent(More)
Searches for neutral Higgs bosons are performed with the 237 pb −1 of data collected in 1999 by the ALEPH detector at LEP, for centre-of-mass energies between 191.6 and 201.6 GeV. These searches apply to Higgs bosons within the context of the Standard Model and its minimal supersymmetric extension (MSSM) as well as to invisibly decaying Higgs bosons. No(More)
The data collected at centre-of-mass energies of 188.6 GeV by ALEPH at LEP, corresponding to an integrated luminosity of 176.2 pb −1 , are analysed in a search for pair-produced charged Higgs bosons H ±. Three analyses are employed to select the τ + ν τ τ − ¯ ν τ , c¯ sτ − ¯ ν τ and c¯ ss¯ c final states. No evidence for a signal is found. Upper limits are(More)
A search has been performed for the Standard Model Higgs boson in the data sample collected with the ALEPH detector at LEP, at centre-of-mass energies up to 209 GeV. An excess of 3 σ beyond the background expectation is found, consistent with the production of the Higgs boson with a mass near 114 GeV/c 2. Much of this excess is seen in the four-jet(More)
Hadronic Z decay data taken with the ALEPH detector at LEP1 are used to measure the three-jet rate as well as moments of various event-shape variables. The ratios of the observables obtained from b-tagged events and from an inclusive sample are determined. The mass of the b quark is extracted from a fit to the measured ratios using a next-to-leading order(More)
The cross sections and forward-backward asymmetries of hadronic and leptonic events produced in e + e − collisions at centre-of-mass energies from 130 to 183 GeV are presented. Results for e + e − , µ + µ − , τ + τ − , q¯ q, b ¯ b and c¯ c production show no significant deviation from the Standard Model predictions. This enables constraints to be set upon(More)
Using approximately 4 million hadronic Z decays recorded with the aleph detector from 1991 through 1995, the lifetime of the b baryon is measured with three independent methods. From the impact parameter distribution of candidate leptons in 1063 events with`? combinations, the average b baryon lifetime is measured to be 1:200:08 0:06 ps. From a sample of(More)
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