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A pair of completely integrated capless preamplifiers (not requiring external capacitance) for MEMS microphones are presented. The devices exploit specific circuit solutions to implement a proper dc biasing of the pre-amplifier and a low frequency (< 1 Hz) high-pass pole. The two solutions adopted are a based on a transistor in the off state (OTP) and a switched-resistor (SRP), respectively. Since the devices are supposed to operate with different silicon microphones, the pre-amplifier gain has to be programmable. In spite of the single ended configuration and independently of the gain, both pre-amplifiers achieve a signal to noise ratio (SNR) lower than -100 dB. The total harmonic distortion (THD) is lower than -80 dB for the OTP and lower than -100 dB for the SRP. The devices are implemented in a 0.18-Î1⁄4m CMOS technology, with a supply voltage of 1.8-V. In both cases the power consumption is 230 Î1⁄4W. The bandwidth of interest ranges from 20 Hz to 20 kHz. Both solutions have variable gain configurations [-6, 0, 6, 12, 18] dB.

Audio interfaces are among the most popular interfaces between man and machines. Such interfaces are based on microphones, whose efficiency expressed in terms of performance/power consumption is becoming one of the crucial parameters for the success on the market. In this chapter, the main specifications of typical microphone interfaces are illustrated to exhibit the advances in their development toward the maximization of their efficiency.

This work lies within SCALTECH28 project, whose main purpose is to investigate the performance of the 28nm technology in terms of signal processing quality, power consumption, and radiation hardness for applications in instrumentation electronics for particle physics with respect to previous technological generations. An additional target is to experimentally evaluate radiation damage effects on single devices and on full circuits to develop rad-models for simulations. A test chip including elementary device arrays and dedicated read-out circuits has been developed and fully characterized. In particular, a capacitance to frequency converter has been integrated to measure the matching between different capacitors of a programmable array. Experimental results show that matching performance is comparable to previous technologies, making the 28nm technology eligible for analog signal processing in front-end circuits for physical experiments and related data converters. Samples have been sent to irradiation facility for high energy experiments compliance verification.

In the Netherlands, the functional approach described in the 2008 European Asphalt Concrete standards was selected, specifying mixtures by their stiffness, fatigue resistance, permanent deformation, moisture sensitivity and limited composition data. The requirements for the functional specifications were based on the existing experience with a large number of mixes. Since the introduction of the standards, unexpected developments like improved performance in all functional tests with increasing RAP content, led to questions about the predictive quality of the laboratory determined functional characteristics for field performance and the potential causes of a mis-match between lab and practice. These questions led to a large, long term project in the Netherlands (NL-LAB) in which the functional characteristics are determined in the process of construction projects. They are determined on (I) material mixed and compacted in the lab, (II) mixed in the plant and compacted in the lab and (III) mixed in the plant and compacted in the road. These tests will eventually provide insight in the effect of mixing and compaction. The pavement sections are monitored in time, to allow the link with pavement performance. The sections will be sampled during their service life to see changes occur in their functional properties. For the road industry, that tries to guarantee pavement performance by accurate selection of materials, the possibility of design information based on both laboratory and in situ results would be beneficial. Two mixes for base layers with different mix compositions and amounts of RAP are analysed using formalistic expressions originating from Design Guide Level II for estimation of various performance indicators. This project uses expressions to analyse the differences between the mixes in the three cases described above. It addresses the possibility of utilizing these expressions during preliminary mix design to guide the selection of mix composition para, Pavement Engineering

Sinds 2008 werken we in Nederland met functionele eigenschappen voor asfalt beton. Hierbij wordt niet zo zeer op het “recept” van het asfalt gestuurd, als wel op de eigenschappen ervan die van belang zijn voor het gedrag in de weg. Binnen het NL-LAB programma wordt de relatie tussen deze functionele eigenschappen en het gedrag in de weg gevalideerd. Hierbij wordt ook gekeken naar de invloed van mengen en verdichten op de functionele eigenschappen. Binnen dit programma is er voor de eerste twee projecten gekeken naar de relatie tussen de mengselsamenstelling en de indirecte treksterkte en weerstand tegen permanente vervorming. Dergelijke relaties zijn in de historie van de wegenbouw vaker met succes gebruikt. Veranderingen in proeven, materialen, mengselsamenstelling en gebruikscondities vragen echter om validatie en calibratie. Het meest recente stelsel van relaties tussen samenstelling en functionele eigenschappen is dat van de Mechanistic Empirical Design Guide. In deze bijdrage wordt beschreven hoe deze relatie worden gebruikt als uitgangspunt voor het koppelen van mengselsamenstelling van twee AC mengsels aan de indirecte treksterkte (ongeconditioneerd) en de weerstand tegen permanente vervorming. Hierbij wordt ook gekeken of het effect van mengen en verdichten zichtbaar is in de data., Pavement Engineering

This paper describes a project that is part of NL-LAB, a larger, long-term program at Delft University of Technology, Netherlands, which aims to establish the predictive capacity of the current European functional tests for Dutch asphalt concrete (AC) mixtures. In this NL-LAB program, the functional characteristics of resistance to rutting (EN 12697-25), fatigue (EN 12679-24), stiffness (EN 12697-26), and moisture sensitivity (EN 12697-12 and EN 12697-23) are determined for specimens that are (a) mixed and compacted in the lab, (b) mixed in the plant and compacted in the lab, and (c) mixed in the plant and compacted in the road. Eventually, these tests will provide insight into the effect of mixing and compaction on the functional characteristics. The project described in this paper focused on the indirect tensile strength (ITS) and the triaxial cyclic compression test for two AC mixes. The properties found for all three stages of preparation were analyzed with the use of formalistic expressions from the NCHRP Design Guide 1-37A, Level 2, for the estimation of performance indicators. This project aimed to see if these relations remained valid for the Comité Européen de Normalisation tests, especially for mixes with high recycled asphalt pavement content. In the Netherlands, 50% reclaimed asphalt pavement is standard. It was found that the NCHRP Design Guide 1-37A expressions fit the Comité Européen de Normalisation test data quite well for the reclaimed asphalt pavement that contained mixes, especially for the ITS. Currently, another two construction projects are being sampled, and the results will be used to validate and improve the relations., Alternative title: COMBINING THE AMERICAN AND EUROPEAN MIX DESIGN APPROACHES: utilization of NCHRP performance indicators for analysis of CEN-test results, Pavement Engineering

Zinc was selected as a priority micronutrient for EURRECA, because there is significant heterogeneity in the Dietary Reference Values (DRVs) across Europe. In addition, the prevalence of inadequate zinc intakes was thought to be high among all population groups worldwide, and the public health concern is considerable. In accordance with the EURRECA consortium principles and protocols, a series of literature reviews were undertaken in order to develop best practice guidelines for assessing dietary zinc intake and zinc status. These were incorporated into subsequent literature search strategies and protocols for studies investigating the relationships between zinc intake, status and health, as well as studies relating to the factorial approach (including bioavailability) for setting dietary recommendations. EMBASE (Ovid), Cochrane Library CENTRAL, and MEDLINE (Ovid) databases were searched for studies published up to February 2010 and collated into a series of Endnote databases that are available for the use of future DRV panels. Meta-analyses of data extracted from these publications were performed where possible in order to address specific questions relating to factors affecting dietary recommendations. This review has highlighted the need for more high quality studies to address gaps in current knowledge, in particular the continued search for a reliable biomarker of zinc status and the influence of genetic polymorphisms on individual dietary requirements. In addition, there is a need to further develop models of the effect of dietary inhibitors of zinc absorption and their impact on population dietary zinc requirements.

An (IC)-C-2 programmable 0.35 mu m CMOS System-on-Chip (SoC) for bi-dimensional gas-sensor arrays providing extended dynamic range read-out with suitable embedded A/D converter and digitally controlled row temperature has been developed. The SoC also features low-power consumption, low-cost production, wide re-configurability and thus large scale compliance with several types of micro-sensors, achieving maximum performance if connected to resistive metal-oxide gas-sensor grids. The CMOS SoC read-out sub-circuit is inspired to laboratory professional electrometers and made up of a current to digital converter plus suitable very low insertion loss analog multiplexers. If connected to a 5x5 gas-sensor array, it features 380 possible measurement configurations. Arbitrary read-out sequences and temperature profiles, in time and in space, in the range [25 degrees C divided by 500 degrees C] may be run through embedded (IC)-C-2 interface and, without requiring calibration circuits, the SoC features over 160dB measured dynamic range in sensor current read-out with a worst-case output rate of 1 reading per second. Concerning instead digital row temperature regulation, the SoC sub-circuit features an accuracy, including ripple, better than 1 degrees C reaching the set-point temperature value in less than 30ms

Objective To review evidence on the associations between vitamin B12 intake and its biomarkers, vitamin B12 intake and its functional health outcomes, and vitamin B12 biomarkers and functional health outcomes. Design A systematic review was conducted by searching electronic databases, until January 2012, using a standardized strategy developed in the EURRECA network. Relevant articles were screened and sorted based on title and abstract, then based on full text, and finally included if they met inclusion criteria. A total of sixteen articles were included in the review. Setting Articles covered four continents: America (n 4), Europe (n 8), Africa (n 1) and Asia (n 3). Subjects Population groups included healthy infants, children and adolescents, and pregnant and lactating women. Results From the total number of 5815 papers retrieved from the initial search, only sixteen were eligible according to the inclusion criteria: five for infants, five for children and adolescents, and six for pregnant and lactating women. Conclusions Only one main conclusion could be extracted from this scarce number of references: a positive association between vitamin B12 intake and serum vitamin B12 in the infant group. Other associations were not reported in the eligible papers or the results were not provided in a consistent manner. The low number of papers that could be included in our systematic review is probably due to the attention that is currently given to research on vitamin B12 in elderly people. Our observations in the current systematic review justify the idea of performing well-designed studies on vitamin B12 in young populations.

The beneficial effect of folic acid supplementation before and shortly after conception is well recognized, whereas the effect of supplementation during the second and third trimesters is controversial and poorly documented. Our aims were to systematically review randomized controlled trials (RCTs) investigating the effect of folate supplementation on birth weight, placental weight and length of gestation and to assess the dose–response relationship between folate intake (folic acid plus dietary folate) and health outcomes. The MEDLINE, EMBASE and Cochrane Library CENTRAL databases were searched from inception to February 2010 for RCTs in which folate intake and health outcomes in pregnancy were investigated. We calculated the overall intake-health regression coefficient ( ß ˆ ) by using random-effects meta-analysis on a loge-loge scale. Data of 10 studies from 8 RCTs were analyzed. We found significant dose–response relationship between folate intake and birth weight (P=0.001), the overall ß ˆ was 0.03 (95% confidence interval (CI): 0.01, 0.05). This relationship indicated 2% increase in birth weight for every two-fold increase in folate intake. In contrast, we did not find any beneficial effect of folate supplementation on placental weight or on length of gestation. There is a paucity of well-conducted RCTs investigating the effect of folate supplementation on health outcomes in pregnancy. The dose–response methodology outlined in the present systematic review may be useful for designing clinical studies on folate supplementation and for developing recommendations for pregnant women.