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Intrauterine growth restriction (IUGR) and fetal growth restriction (FGR) are pregnancy complications associated with morbidity in later life. Despite a growing body of evidence from current research on developmental origins of health and disease (DOHaD), little information is currently provided to parents on long-term metabolic, cardiovascular and neurologic consequences. As parents strongly rely on internet-based health-related information, we examined the quality of information on IUGR/FGR sequelae and DOHaD in webpages used by laypersons. Simulating non-clinicians experience, we entered the terms ‘IUGR consequences’ and ‘FGR consequences’ into Google and Yahoo search engines. The quality of the top search-hits was analyzed with regard to the certification through the Health On the Net Foundation (HON), currentness of cited references, while reliability of information and DOHaD-related consequences were assessed via the DISCERN Plus score (DPS). Overall the citation status was not up-to-date and only a few websites were HON-certified. The results of our analysis showed a dichotomy between the growing body of evidence regarding IUGR/FGR-related sequelae and lack of current guidelines, leaving parents without clear directions. Furthermore, detailed information on the concept of DOHaD is not provided. These findings emphasize the responsibility of the individual physician for providing advice on IUGR/FGR-related sequelae, monitoring and follow-up.
High-performance SiGe HBTs and advancements in packaging processes have enabled system-in-package (SiP) designs for millimeter-wave applications. This paper presents a 122-GHz bistatic frequency modulated continuous wave (FMCW) radar SiP. The intended applications for the SiP are short-range distance and angular position measurements as well as communication links between cooperative radar stations. The chip is realized in a 130-nm SiGe BiCMOS technology and is based on a fully differential frequency-multiplier chain with in phase quadrature phase receiver and a binary phase shift keying modulator in the transmit chain. On-wafer measurement results show a maximum transmit output power of 2.7 dBm and a receiver gain of 11 dB. The chip consumes a DC power of 570 mW at a supply voltage of 3.3 V. The fabricated chip is integrated in an embedded wafer level ball grid array (eWLB) package. Transmit/receive rhombic antenna arrays with eight elements are designed in two eWLB packages with and without backside metal, with a measured peak gain of 11 dBi. The transceiver chip size is 1.8 mm × 2 mm, while the package size is 12 mm × 6 mm, respectively. FMCW measurements have been conducted with a sweep bandwidth of up to 17 GHz and a measured range resolution of 1.5 cm has been demonstrated. 2D positions of multiple targets have been computed using two coherently linked radar stations.
Idiopathic intrauterine growth restriction (IUGR) is a result of impaired placental nutrient supply. Newborns with IUGR exhibiting postnatal catch-up growth are of higher risk for cardiovascular and metabolic co-morbidities in adult life. Mammalian target of rapamycin (mTOR) was recently shown to function as a placental nutrient sensor. Thus, we determined possible correlations of members of the placental mTOR signaling cascade with auxologic parameters of postnatal growth. The protein expression and activity of mTOR-pathway signaling components, Akt, AMP-activated protein kinase α, mTOR, p70S6kinase1 and insulin receptor substrate-1 were analysed via western blotting in IUGR v. matched appropriate-for-gestational age (AGA) placentas. Moreover, mTOR was immunohistochemically stained in placental sections. Data from western blot analyses were correlated with retrospective auxological follow-up data at 1 year of age. We found significant catch-up growth in the 1st year of life in the IUGR group. MTOR and its activated form are immunohistochemically detected in multiple placental compartments. We identified correlations of placental mTOR-pathway signaling components to auxological data at birth and at 1 year of life in IUGR. Analysis of the protein expression and phosphorylation level of mTOR-pathway components in IUGR and AGA placentas postpartum, however, did not reveal pathognomonic changes. Our findings suggest that the level of activated mTOR correlates with early catch-up growth following IUGR. However, the complexity of signals converging at the mTOR nexus and its cellular distribution pattern seem to limit its potential as biomarker in this setting.
Embedded wafer-level ball grid array (eWLB) is investigated as a low-cost plastic package for automotive radar applications in the 76–81 GHz range. Low transmission losses from chip to package and board are achieved by appropriate circuit and package design. Special measures are taken to effectively remove the heat from the package and to optimize the package process to achieve automotive quality targets. A 77 GHz radar chip set in eWLB package is developed, which can be applied on the system board using standard solder reflow assembly. These radar MMICs provide excellent radio frequency (RF) performance for the next generation automotive radar sensors. The potential for even higher system integration is shown by a radar transceiver with antennas integrated in the eWLB package. These results demonstrate that eWLB technology is an attractive candidate to realize low-cost radar systems and to enable radar safety affordable for everyone in the near future.
The crystallization process of SrxBiyTa2O5+x+3y/2 thin films grown by metalorganic chemical vapor deposition was investigated. Phase formation and crystal growth is greatly affected by the film composition and crystallization temperature. Phase diagrams for varying Sr or Bi contents were determined as a function of the crystallization temperature. The higher the Sr or Bi content in the film, the lower the phase transition temperature from the amorphous to the fluorite-type phase and from the fluorite-type to the Bi-layered Aurivillius phase. Low Sr and Bi contents support pyrochlore-type phase formation as a second phase. During annealing, excess Bi is not lost due to evaporation, but due to migration to the bottom electrode. Contrary to the fluorite-type phase, the Aurivillius phase is not able to incorporate the excess of Bi atoms. Decreasing grain size and pyrochlore-type phase formation entail decreasing remanent polarization.
Ferroelectric random access memories (FeRAMs) are new types of memories especially suitable for mobile applications due to their unique properties such as nonvolatility, small DRAM - like cell size, fast read and write as well as low voltage / low power behavior. Although standard CMOS processes can be used for frontend and backend / metallization processes, FeRAM technology development has to overcome major challenges due to new materials used for capacitor formation. In this paper, advantages and disadvantages of different ferroelectric materials and major development issues for high density applications are discussed. Results of a 0.5μm ferroelectric process using SrBi2Ta2O9 (SBT) as ferroelectric layer, Pt as electrode material, and 2-layer tungsten / aluminum metallization are discussed.
Thin films of high-k dielectric/ferroelectric materials such as BaxSr1−xTiO3 (BST), PbZrxTi1−xO3 (PZT) and SrBi2Ta2O9 (SBT) are currently investigated for integration into high-density CMOS technology. Characterization of these materials by SPM techniques combines imaging of the morphology and microstructure of these films and recording of various electrical parameters at the same local area. Using commercial equipment we have investigated electrical properties such as polarization and leakage current behavior of MOD/MOCVD SBT by applying electrostatic force microscopy (EFM) and conducting atomic force microscopy (CAFM). After applying bias voltages of a few volts across the SBT films between the scanning tip and the lower electrode completely polarized/reverse polarized SBT layers could be observed by EFM. Even single crystallite polarization was imaged. However, unexpectedly some films showed incomplete polarization, which may be caused by local electrical field effects. Images taken by C-AFM displayed enhancement of leakage currents in grain boundary regions, in particular at depressions between adjacent crystallites. The results achieved demonstrate that SPM techniques operated in a variety of imaging and measuring modes, provide a tremendous potential in the elucidation of the microscopic properties of high-k materials.
The imprint behavior of CSD processed SrBi2Ta2O9 (SBT) thin films has been investigated as a function of time, applied bias, illumination with band gap light and post anneal under different oxygen partial pressures. Applying a bias in the direction of the polarization enhances the tendency of the capacitor to exhibit a voltage shift as well as illuminating the poled capacitor with band gap light. Post anneal after top electrode deposition and patterning under slightly reducing atmospheres does not affect the imprint rate. From these experimental results, a model is presented which explains the imprint behavior of SBT films by transport of electronic charges from the electrodes into the film and subsequent trapping of these charges near the interface.
In order to ensure the quality of the source catalogue derived from the SASS processing an automatic as well as a visual screening procedure was applied to 1378 survey fields. Most (94%) of the 18,811 sources were confirmed by this screening process. The rest is flagged for various reasons. Broad band images are available for a subset of the flagged sources. Details of the screening process can be found at www.rosat.mpe-garching.mpg.de/survey/rass-bsc/doc.html.
This work presents a survey of the mechanisms of the polarization in ferroelectric thin films which are relevant for application in non-volatile ferroelectric memories (FeRAM). Since the integration of these materials in new memory generations requires small structures and therefore a maximum utilization of the switchable polarization, the distinction between the several polarization mechanisms is of specific interest. Standard characterization methods, such as hysteresis loops, C-V measurements and fast pulse switching tests are evaluated and used to distinguish between the reversible and irreversible contributions to the total polarization. The respective contributions are described qualitatively and demonstrated at spin-coated SrBiTa2O9 thin films and compared with Pb(Zr,Ti)O3 films. Additionally, a method is described to obtain the static hysteresis curve, a precise characterization of the polarization which does not depend on the measuring frequency. These data are compared with C-V measurements. It is shown that the standard dynamic hysteresis curve reveals misleading statements about the remanent polarization and the coercive voltage.
This chapter provides the indications to form a clear idea of the essential features of the prehistoric Iranian calendar. Hundreds of iconographies found on seals and vases from all over Iran and Mesopotamia demonstrate that such a continuity actually existed. The chapter mentions some typical features observable time and again that indicate terrestrialism and interpretation in characterizing the historical period. In late Babylonian times the first month of the lunisolar year, Nisannu, was the one whose neomenia occurred about the time of spring equinox. In the Later Avestan calendar, four of the month names, called after Old Iranian deities including Tistrya-Sirius, were taken over. The coincidences between month and day names were duly celebrated by festivals. Among them, two seem of special interest because they may reflect, as pointed out by Taqizadeh, the astronomical situation at the time of the introduction of the Magian day-names, for example the alleged 'reform' of 441 BC.