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This paper presents a comparison of chip connections using aerosol jet (AJ) and bond technology on low-cost printed circuit board (PCB) substrates. First, the behavior of the used gap filler material and the used silver ink for AJ technology on PCBs are characterized. In addition to comparing the radio frequency (RF) performance (DC to 67 GHz) of the two technologies, the mechanical stability is also compared. While the AJ technology transitions score above all for their RF performance and the lower requirements (surface finish, pad size, and adhesion) on the PCB, the bonding technology has clear advantages, especially with a different coefficient of thermal expansion values of the substrates to be connected. Finally, the measurement results of a complete package are shown, whereby the chip connection is realized once by means of AJ and once by bonding wires.
The Azerbaijani, Azerbaijanian or Azeri language belongs to the western group of the southwestern, or Oghuz, branch of the Turkic language family and is mainly spoken in Azerbaijan and Iran. Azerbaijani is the official language of the Republic of Azerbaijan and over 80% of its population use it as their first language (Johanson 2010). Among non-Persian languages in Iran, Azerbaijani, with approximately 15–20 million native speakers, has the largest number of speakers (Crystal 2010). In total, more than 50 million people speak Azerbaijani (Khalilzadeh 2013).
The determination of effective temperatures of very hot central stars (Teff > 70 000 K) by model atmosphere analyses of optical H and He line profiles is afflicted with considerable uncertainty, primarily due to the lack of neutral helium lines. Ionization balances of metals, accessible only with UV lines, allow more precise temperature estimates. The potential of iron lines is pointed out. At the same time iron and other metal abundances, hardly investigated until today, may be derived from UV spectra. We describe recent HST spectroscopy performed for this purpose.
A search for iron lines in FUV spectra of the hottest H-deficient central stars (PG1159-type, Teff >100000 K) taken with FUSE was unsuccessful. The derived deficiency is interpreted in terms of iron depletion due to n-capture nucleosynthesis in intershell matter, which is now exposed at the stellar surface as a consequence of a late He shell flash.
FUSE high resolution spectra of two PG1159 type central stars (K1-16 and NGC 7094) have revealed an unexpected iron deficiency of at least 1 or 2 dex (Miksa et al. 2002). Here we present early results of FUSE spectroscopy of the CSPN Abell 78. It is shown that iron is strongly deficient in this star, too.
Previous investigations on hydrogen-rich white dwarfs generally yield only very small rotational velocities (v sin i). We have analyzed line profiles in high-resolution optical spectra of eight hydrogen-deficient (pre-) white dwarfs and find deviations from the dominant Stark line broadening in five cases which, interpreted as an effect of stellar rotation, indicate projected rotational velocities of 40 – 70 km s–1. For the three least luminous stars upper limits of v sin i = 15 – 25 km s–1 could be derived only. The resulting velocities correlate with luminosity and mass. However, since the mass-loss rate is correlated to the luminosity of a star, the observed line profiles may be affected by a stellar wind as well. In the case of RX J2117.1+3412, this would solve discrepancies to results of pulsational modeling (v sin i ≈ 0).
Plant invasions in tropical agricultural landscapes have been poorly studied so far. Here, we use plot data collected in 2015 in the La Gamba valley in southern Costa Rica to analyse the spread of two invasive alien species (Hydrilla verticillata, Hedychium coronarium) on the landscape level. In total, we recorded the aquatic H. verticillata, which was locally introduced into the La Gamba valley in 2005, in 26% of all plots (size: 15 m2), while H. coronarium, which occurs along water courses, was recorded in 80% of all plots (size: 25 m2). Generalized Linear Models (GLMs) showed that the habitat type invaded and shading had no significant effect on H. verticillata presence and abundance. However, proximity to the point of local introduction and habitat diversity in the adjacent landscape did positively affect its presence. For H. coronarium, GLMs showed a significant correlation with the invaded habitat type. The probability of H. coronarium presence was highest in herbaceous vegetation and cover was higher compared with other habitats. There was no effect on native plant species richness and cover by H. verticillata, while H. coronarium exerted a negative impact on herbaceous plant species number and, in particular, cover. Hydrilla verticillata is a rather recent addition to the local alien flora, and thus dispersal limitation still restricts its local range. Compared with observed rates of spread in other regions, spread velocity within the first decade of its local presence was low. In contrast, H. coronarium has been locally present for a substantially longer time period. This species encounters suitable habitat conditions in herbaceous vegetation along water courses, where it builds up dense clonal stands which negatively affect herbaceous vegetation. Our results show that while both study species are invasive in Central American lowlands, their local abundance and impacts on native vegetation may differ profoundly.
We report on our NLTE model atmosphere analyses of PG 1159 stars. The results enable us to confine the location of the GWVir instability region in the Hertzsprung-Russell diagram. The analysis of a spectrum of the non-pulsator PG 1520+525 taken with the EUVE satellite in comparison with HST data of the pulsating protoype PG 1159-035 (=GW Vir) locates the blue edge of the instability strip near Teff=140 000 K for stars in the respective luminosity range.
We present the realization of a cooperative radar system for ranging applications with integrated data-transmission capability. The simultaneous transmission is performed by the radar-hardware without the necessity of additional components or an auxiliary data-link. Therefore, the data are directly embedded in the transmitted chirp of a frequency-modulated continuous-wave radar sensor. A second station, acting as receiver, uses an identical, but unmodulated chirp for down-conversion. The resulting signal then is processed by a non-coherent demodulator setup, extracting the communication data. Measurement results from transmission of messages with different bit-rates are shown. By utilizing existing radar-hardware a transmission rate of up to 256 kbps is possible, without the need of a dedicated transceiver. Additionally, a method to optimize the ranging results by variable distribution of the available signal power between distance-measurement and communication system is presented.
This paper presents a position gauging system of welding joints. While the principle measurement concept was already introduced by Schrattenecker et al. in 2014, here it is focused on different types of practically used welding materials. The sensor used is based on the frequency-modulated continuous-wave principle operating in the W-band. Position estimation (PoE) of different welding geometries is carried out with polarimetric scattering effects introduced by geometrical discontinuities. For the real-time calculation of the signal models a field simulation tool we developed is used. Aside from a variety of geometries, we introduce a geometrical optimization approach that increases the achievable accuracy of the measurement concept. The optimization and PoE of the different welding materials were examined in various simulations and the results were verified by measurements in the laboratory and in an industrial environment. Simulation and measurement were in good agreement.
We present the implementation of a cooperative radar system on a gantry rail crane for distance measurements in an industrial environment. The measurement approach is based on the dual-ramp frequency-modulated continuous-wave principle, using identical sensor-nodes at the endpoints of the range of interest. Pseudo-range information is exchanged via a dedicated data-link between these stations. At the sensor-node a flexible high-performance signal processing and remote management engine is implemented. The system setup is controlled by a single host-PC, which is used as a man–machine interface for configuration of the remotely controlled measurement stations, system surveillance, and visualization of the measurement data. Indoor characterization of the developed hardware is sufficient for an efficient calibration of the system, minimizing distance offsets. On-site measurements at distances up to 1000 m with an accuracy better than 2 cm confirm the performance of the ranging system. Furthermore, the results are verified by simulation.
The efficacy of psychopharmacological treatments has been called into question. Psychiatrists are unfamiliar with the effectiveness of common medical drugs.
To put the efficacy of psychiatric drugs into the perspective of that of major medical drugs.
We searched Medline and the Cochrane Library for systematic reviews on the efficacy of drugs compared with placebo for common medical and psychiatric disorders, and systematically presented the effect sizes for primary efficacy outcomes.
We included 94 meta-analyses (48 drugs in 20 medical diseases, 16 drugs in 8 psychiatric disorders). There were some general medical drugs with clearly higher effect sizes than the psychotropic agents, but the psychiatric drugs were not generally less efficacious than other drugs.
Any comparison of different outcomes in different diseases can only serve the purpose of a qualitative perspective. The increment of improvement by drug over placebo must be viewed in the context of the disease's seriousness, suffering induced, natural course, duration, outcomes, adverse events and societal values.
Revisiting the classical acoustics problem of rectangular side-branch cavities in a two-dimensional duct of infinite length, we use the finite-element method to numerically compute the acoustic resonances as well as the sound transmission and reflection for an incoming fundamental duct mode. To satisfy the requirement of outgoing waves in the far field, we use two different forms of absorbing boundary conditions, namely the complex scaling method and the Hardy space method. In general, the resonances are damped due to radiation losses, but there also exist various types of localized trapped modes with nominally zero radiation loss. The most common type of trapped mode is antisymmetric about the duct axis and becomes quasi-trapped with very low damping if the symmetry about the duct axis is broken. In this case a Fano resonance results, with resonance and antiresonance features and drastic changes in the sound transmission and reflection coefficients. Two other types of trapped modes, termed embedded trapped modes, result from the interaction of neighbouring modes or Fabry–Pérot interference in multi-cavity systems. These embedded trapped modes occur only for very particular geometry parameters and frequencies and become highly localized quasi-trapped modes as soon as the geometry is perturbed. We show that all three types of trapped modes are possible in duct–cavity systems and that embedded trapped modes continue to exist when a cavity is moved off centre. If several cavities interact, the single-cavity trapped mode splits into several trapped supermodes, which might be useful for the design of low-frequency acoustic filters.
In the context of ferromagnetic spin-coupling in dilute magnetic semiconductors, we present optical investigations on Mg co-doped GaMnN and Fe doped GaN. A complex luminescence feature occurring in Mg co-doped GaMnN around 1 eV was previously attributed to the internal 4T2(F)—4T1(F) transition of Mn4+ involved in different complexes. Selective excitation studies indicate the presence of at least three different complexes. Photoluminescence excitation spectra suggest that the internal Mn3+ transition may represent an excitation mechanism. Magneto photoluminescence spectra indicate equal g values for the ground and excited state. Low temperature infrared absorption spectra of Fe doped GaN allow to unambiguously establish the electronic structure of the Fe2+ center in GaN. Our results suggest that the Fe2+(5T2) state is stabilized against Jahn-Teller coupling by the reduced site-symmetry of the hexagonal lattice.
The carrier-phonon interaction in self-organized In(Ga)As/GaAs quantum dots is investigated under resonant excitation of the ground-state transition. Different phonon-coupled processes are observed. The distinction between Raman scattering and hot-luminescence process has been resolved by time-dependent photoluminescence measurements. The quantum dot LO (33.8 meV) as well as an interface (36.5 meV) phonon mode is observed by resonant Raman scattering. For the QD LO phonon mode, a very short radiative lifetime of 10 ps was found.
Initiation of pathways that lead to proliferation and chemoresistance by Toll-like receptors (TLRs) is an important factor in cancer progression. Here, we show the response of human cancer cells to TLR signaling inevitably linked to tumor biology. The approach is based on tailored multifunctional magnetic nanoparticles equipped with pathogen-derived ligands (CpG) functioning as TLR agonists (molecular component) to investigate the impact of transcription factor immune activation on human cancer cells. Magnetic nanoparticles (MnO and bifunctional Au-MnO) particles were covalently coated with a multifunctional polymer, displaying no cytotoxicity, to being able to enter cells while carrying foreign DNA (unmethylated CpG) to recognize intracellular TLR 9. Both, the particle and the nucleic acid are tagged with fluorescent markers for simultaneous visualization inside the cell. Apart from optical imaging, the magnetism of the particles also allows magnetic resonance imaging of organisms.