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The characterisation of the fabrication process to develop freestanding SU-8 structures integrated in printing circuit board in microelectromechanical systems (PCBMEMS) technology is presented. SU-8 microcantilevers, microbridges, microchannels and micromembranes have been fabricated following the described procedure. Adherence between FR4 substrate and SU-8 has been examined using the destructive blister method, evaluating the surface energy. Residual thermal stress has also been analysed for this integration and compared when using other substrates. Moreover, an estimation of the copper wet etching with cupric chloride has been performed in order to understand how this isotropic etching affects the geometry of the copper structures. Finally, stiction has been observed and examined, estimating the adhesion energy responsible for this effect. [ABSTRACT FROM AUTHOR]

In this paper, a single-use and unidirectional microvalve with low consumption of energy for PCB-based microfluidic platforms is reported. Its activation is easy because it works as a fuse. The fabrication process of the device is based on PCB technology and a typical SU-8 process, using the PCB as a substrate and SU-8 for the microfluidic channels and chambers. The microvalve is intended to be used to impulse small volumes of fluids and it has been designed to be highly integrable in PCB-based microfluidic platforms. The proposed device has been fabricated, integrated and tested in a general purpose microfluidic circuit, resulting in a low activation time, of about 100 μs, and a low consumption of energy, with a maximum of 27 mJ. These results show a significant improvement because the energy consumption is about 84% lower and the time response is about four orders of magnitude shorter if compared with similar microvalves for impulsion of fluids on PCB-based platforms. [ABSTRACT FROM AUTHOR]

The emergent IMS (Internet Protocol Multimedia Subsystem) technology appears to improve the current communication technologies. Its characteristics, such as Quality of Service (QoS), make it an advantageous system for innovative applications. Providing integrated services to users is one of the main reasons for the existence of IMS. Operators provide the technology as an open source, to be able to use services developed by researchers. Combining and integrating them, users will receive completely new services. Our proposal of use for IMS is the development of a telemedicine platform, designed to support not only remote biological signal monitoring, but value-added services for diagnosis and medical care, both of these working in real time.

This paper proposes an iterative procedure for the determination of parameters and working conditions of biomedical signal processing algorithms. A systematization of the process required to determine the parameters is proposed, avoiding "trial and error" tests, and considering all the specific requirements of a Telemedicine system, such as reliability and guaranteed signal reconstruction quality. An application of the method is included, also, focusing on ECG processing. Hardware platform Biolet(E) is designed for validation in an electronic implementation.

This paper presents the MIMOSA architecture and development platform to create Ambient Intelligence applications. MIMOSA achieves this objective by developing a personal mobile-device centric architecture and open technology platform where microsystem technology is the key enabling technology for their realization due to its low-cost, low power consumption, and small size. This paper focuses the demonstration activities carried out in the field of health care. MIMOSA project is a European level initiative involving 15 enterprises and research institutions and universities.

A cytogenetic study of early bovine embryos (2-16 blastomeres) produced in vitro was conducted to determine the incidence of embryos carrying chromosome anomalies. The embryos were produced from immature oocytes matured in vitro and fertilized by sperm prepared using the Percoll density gradient method. Slides were prepared according to an 'air drying' technique and the chromosomal complement of embryos was studied by Giemsa-staining. Approximately 57% of prepared embryos were suitable for analysis. The results revealed that 18% of cytogenetically analysed embryos presented chromosomal anomalies, including haploidy (8%), aneuploidy (2%) and polyploidy (8%). Our results were compared to the results of other studies in cattle and other domestic animals., (Copyright 1999 Harcourt Publishers Ltd.)

The present work describes a cytogenetic study of in vitro-matured bovine oocytes designed to analyze the incidence of diploid oocytes induced by concentration of serum in the culture medium, follicle size, culture temperature and incubation time. In Experiment 1, immature follicular oocytes from follicles of the same size were cultured for 24 h in TCM-199 supplemented with increasing concentrations 0, 10, 20 and 50% of estrous cow serum (ECS). In Experiment 2, immature oocytes harvested from follicles of different sizes were cultured for 24 h in TCM-199 supplemented with 20% ECS at 39 degrees C in 5% CO2. In Experiment 3, immature follicular oocytes were matured in TCM-199 supplemented with 20% ECS at 2 different temperatures (37 degrees C or 39 degrees C) in 5% CO2. In Experiment 4, immature oocytes were matured over 4 different incubation times (24, 36 and 48 h) in TCM-199 supplemented with 20% ECS in 5% CO2. The highest concentration (50%) of ECS supplement in the culture medium induced the highest incidence of diploid oocytes. This incidence of diploid oocytes matured in vitro was higher in oocytes from follicles with a diameter between 11 and 15 mm. Finally, lower culture temperature (37 degrees C) and prolonged incubation time (48 h) also significantly (P<0.01) increased the percentage of diploid oocytes.

Low power He-Ne laser irradiation was applied to immature bovine oocytes to investigate the incidence of unreduced oocytes (diploid oocytes) during the first meiotic division in vitro. Immature bovine oocytes from cows killed at a slaughterhouse were irradiated with He-Ne laser irradiation at 0.05 and 0.25 J/cm(2) exposures. An oocyte group was left untreated serving as the control group. All oocytes were matured in TCM-199 medium supplemented with 10% fetal calf serum (FCS). Unreduced oocyte percentages obtained in the irradiated oocytes group were significantly higher (p<0.01 and p<0.001, respectively) than those of the control group. Furthermore, the laser-treated oocytes showed a degeneration rate significantly higher (p<0.01 and p<0.001, respectively) than those observed in the control group. It is concluded that the application of He-Ne laser irradiation at 0.05 and 0.25 J/cm(2) exposures increased the incidence of unreduced oocytes and the percentage of degenerated oocytes during the in vitro meiosis process of immature bovine oocytes.

The purpose of this study was to determine the effect of He-Ne laser irradiation (632.8 nm, 10 mW) on the induction of acrosome reaction and mortality in bull sperm cells in comparison with two important capacitation agents; calcium and heparin. Frozen-thawed bull sperm cells were washed in percoll gradient and suspended at a concentration of 1 x 10(6) ml-1 in sp-TALP medium, capacitated in the presence of 2 mM CaCl2, 10 micrograms ml-1 heparin, or irradiated at fluences from 2 to 16 J cm-2, and incubated for 0, 30, 60 and 90 minutes. At the end of the incubation period, the percentage of sperm that were acrosome-reacted and dead was determined. The results obtained indicated that laser irradiation at all fluences produced a significant increase (p < 0.001) in the percentage of sperm cells that were acrosome reacted, and a significant decrease (p < 0.001) in the percentage of dead sperm at 90 minutes of incubation in comparison to other capacitation agents and the control group. The percentage of sperm cells with acrosome reaction was increased with increasing fluences of laser irradiation and time of incubation. It is conclude that the application of He-Ne laser irradiation at fluences from 2 to 16 J cm-2 induced the acrosome reaction and decreased the sperm mortality percentage in vitro of bull sperm cells.

The effects of laser light on the cellular DNA have not been extensively characterized. Low-power laser sources, such as the helium-neon (He-Ne) laser with a wavelength of 632.8 nm, have been found to produce photobiological and photodamage effects with evidence of interference with cell replication. We have investigated the effects of He-Ne laser irradiation on sister chromatid exchange (SCE) frequencies in sheep peripheral blood mononuclear cells (PBMC). Cultured cells were irradiated once at 6 selected energy intensities of laser irradiation and then stimulated with pokeweed mitogen and cultured in the presence of 5-bromodeoxyuridine (BrdUrd). The frequency of SCEs of both irradiated and non-irradiated cells were analyzed. The mean SCE of irradiated cells significantly increased with growing energy density up to a laser dose of 24 J/cm2, whereas after an energy density of 24 J/cm2, the SCE frequency decreased with increasing energy densities. We concluded that the application of He-Ne laser irradiation at energy densities ranging from 2 to 96 J/cm2 produced a different effect on SCE frequency in sheep PBMC in vitro.

Three experiments were carried out to investigate whether bovine amniotic fluid (BAF), when added as a protein supplement to the maturation medium, supports the in vitro maturation of pre-ovulatory bovine oocytes. In the first experiment, the medium was supplemented with three different concentrations of the BAF (10, 20 and 50%, respectively). In the second experiment, the effects of a combination of two protein supplements BAF plus oestrus cow serum (BAF-OCS) and BAF plus bovine follicular fluid (BAF-BFF), on the in vitro oocyte maturation rates were evaluated. In the third experiment, the effects of three different protein supplements (BAF, OCS, and BFF) on the oocyte maturation percentages were compared. Maturation rates at the metaphase II stage, following supplementation with 20% BAF (77%) and 10% BAF (68%) were significantly higher (P < 0.001 and P < 0.05, respectively) than those resulting from supplementation with 50% BAF (44%). Significant differences between the 10% BAF and 20% BAF treatments were not observed. Significant differences were, however, found between the BAF-OCS treatment (57%) and the BAF-BFF treatment (50%). The results obtained from the BAF and the OCS treatments (77 and 78%, respectively) were significantly higher (P < 0.05) than when BFF (60%) was used. It is concluded that supplementation of the in vitro maturation medium of pre-ovulatory bovine oocytes with BAF provides important levels of proteins and growth factors responsible for nuclear and cytoplasmic development.

This work was designed to evaluate the influence of different types of media supplements in the maturation of preovulatory oocytes in cattle. We studied 4 different supplements: serum from estrous cattle (ECS), serum from fetal calves (FCS), amniotic fluid from cattle (bAF) and follicular fluid from cattle (bFF). Preovulatory bovine oocytes recovered from ovaries of mature cows after slaughter were cultured for 24 h in TCM-199 medium containing 20% of one of these protein supplements. The percentages of oocyte maturation were significantly higher (P < 0.001) in ECS (78%), FCS (79%) and bAF (77%) than in bFF (52%). These data indicate that supplementation with ECS, FCS or bFF is adequate for maturation of bovine oocytes without addition of other compounds.

The neural signal carried by the abducens nerve during eye fixations was simulated. The neural discharge was defined by the number of spikes carried by the abducens nerve within each ms. Calculations were based on real neurophysiological data. The computed neural signal showed frequency histograms and variance/mean ratios typical of a Poisson distribution. A peak was obtained in the power spectral density function of the simulated neural signal. This peak appeared in the frequency range corresponding to the firing rate of single motoneurons for each eye position. It remained as a broad spectral peak after filtering by a second-order differential equation simulating the ocular mechanics. The obtained spectra are similar to the described power spectral density function of eye position recordings. Present results add evidence of a possible neural basis for ocular tremor.