Struktur und Eigenschaften gepfropfter Kartoffelstärke. III. Mikrostruktur und Bindungsverhältnisse in der Pfropf-co-polymer-Phase

Structure and Properties of Grafted Potatoe Starch. III. Microstructure and Interchain Bonds in the Graft-Copolymer-Phase Graft copolymers of polyacrylic acid and polymethacrylic acid, grafted according to the Scott-xanthation process were investigated. By combining different optical methods information could be obtained about interchain bonds in the copolymer phase. From frequency, shape and intensity of different infra-red absorption bands it could be concluded that there are hydrogen bridges from the carboxylic groups of the side chain polymer to the hydroxyl groups of the backbone-polysaccharid. These bonds lead to a crystalline copolymer phase which is different from starch and have an influence on the configuration of the polysaccharid chains in solution.     

Relation between injection barrier and contact resistance in top-contact organic thin-film transistors

We theoretically investigate the carrier injection into top-contact bottom-gate organic thin film transistors. By means of a two-dimensional drift–diffusion model, we explicitly consider thermionic and tunneling injection in combination with subsequent carrier transport into the device. Based on numerical simulations with this model, we determine the contact resistance as a function of the nominal hole injection barrier height and temperature. Depending on the barrier height or the operating temperature, we find three distinct injection regimes. Our work reveals that in all three regimes self-regulating processes exist due to which the influx of current is adjusted according to the needs of the channel at the given point of operation.     

A survey of autonomic networking architectures: towards a Unified Management Framework

Academic and industrial research initiatives have sought to make fully autonomic networks a reality. Some of these initiatives pursued a holistic approach, while others focused on setting up functionalities for specific networking domains. These efforts did not succeed in being extensively deployed, because the goals of network operators were not satisfactorily met. These goals include unification of management operations, enablement of end‐to‐end management and enhancement of the overall system performance in a trusted way, while reducing management cost. In this paper, we analyse a set of existing autonomic management architectures and frameworks with respect to a selected set of criteria. We then identify missing parts and challenges and propose a framework to unify the most promising attributes towards a novel approach of realization of autonomic networking management. We call this proposal Unified Management Framework (UMF). Copyright © 2013 John Wiley & Sons, Ltd.     

High quality LTCC resonator for voltage-controlled oscillator

Design and technology of microwave conductor lines embedded in low-temperature cofired ceramic (LTCC) multilayer substrates are summarized with a focus on achieving the highest possible quality (Q) factor for a given line inductance. The work was initiated to test the integrability of base station voltage-controlled oscillators (VCOs) in ceramic multilayer substrates. This approach leads to a miniaturization of current versions by a factor of 2 to 4. However, base station specifications for phase noise and hence resonator Q are extremely demanding. Therefore, both the design and the processing technology were optimized. By choosing a twin-line design with two parallel lines vertically separated by a single LTCC layer, Q factors of 90 and 180 have been achieved for integrated 5.5 nH inductors at frequencies of 640 MHz and 1650 MHz, respectively. Application of this result to VCO modules in standard LTCC technology already yields low phase noise levels, e.g., -136 dBc/Hz at 100 kHz offset, which is suitable for base station applications. However, further noise reduction is expected from a dedicated high Q fabrication process that uses conventional via punching and filling steps to replace the ceramic material between the two lines by conductive silver paste. This raises the Q to 120 and 200, respectively, at the two frequencies and adds extra degrees of freedom to LTCC design for low-loss wireless solutions.     

Radiometrisches Verfahren für die Holzsortierung

Grading according to DIN 4074 (quality specifications for coniferous sawn timber) is of great importance both for the security of timber structures and the economic use of the raw timber. According to this standard, timber grading is based on visual characteristics. In order to objectify timber grading as far as possible, great efforts have been made to achieve timber grading by machines. GreCon, Alfeld, has developed a procedure to determine the density of timber and thus even its content of knots by isotopic γ-radiation. Tests proved that this procedure is suitable for grading of boards and planks. The results show a good correspondence between mean bending strength of machine graded and visually graded timber according to DIN 4074. It is furthermore possible to apply this procedure to other grading rules, for instance the ECE-recommendations.     

Subjective Effects of Variable Delay and Speech Clipping in Dynamically Managed Voice Systems

The purpose of this paper is to examine speech impairments likely to arise in dynamically managed voice (DMV) systems. DMV systems utilize speech activity detection to exploit speech idle time and variable bit rate coding to exploit nonstationary speech statistics. The emphasis here is on systems using speech detection. This processing introduces two impairments not commonly found in traditional communication systems variable Speech burst delay and speech clipping. Simulations of these impairments were implemented, and formal subjective testing was performed to assess subjects' reactions to a range of impairment levels. Emphasis was on formal subjective listening tests and customer opinion of speech quality as defined by a rating scale. The test conditions are applicable to general telephony, where relatively high speech quality is required. Results on variable speech burst delay and front-end and midspeech burst clipping are presented. These results serve as input to the design process and to the establishment of performance guidelines for DMV systems.     

Narrating emotional events in schizophrenia.

Research has indicated that schizophrenia patients report similar amounts of experienced emotion in response to emotional material compared with nonpatients. However, less is known about how schizophrenia patients describe and make sense of their emotional life events. We adopted a narrative approach to investigate schizophrenia patients' renderings of their emotional life experiences. In Study 1, patients' (n = 42) positive and negative narratives were similarly personal, tellable, engaged, and appropriate. However, negative narratives were less grammatically clear than positive narratives, and positive narratives were more likely to involve other people than negative narratives. In Study 2, emotional (positive and negative) narratives were less tellable and detached, yet more linear and social compared with neutral narratives for both schizophrenia patients (n = 24) and healthy controls (n = 19). However, patients' narratives about emotional life events were less appropriate to context and less linear, and patients' narratives, whether emotional or not, were less tellable and more detached compared with controls' narratives. Although schizophrenia patients are capable of recounting life events that trigger different emotions, the telling of these life events is fraught with difficulty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characterisation of L-[3H]glutamate binding to fresh and frozen crude plasma membranes isolated from cerebral cortex of adult rats

Specific [3H]glutamate binding to fresh crude plasma membranes (CPMs) was compared with binding to frozen CPMs and the optimal conditions for the binding to frozen CPMs isolated from cerebral cortex of adult rats were determined. Freezing reduced [3H]glutamate binding (3.5-fold), and pre-incubation of previously frozen membranes followed by three washes increased binding (4.5-fold) when compared to fresh samples. CPMs washed once, pre-incubated at 37 degrees C and washed 3 times was adopted as the most adequate condition for the binding assay of frozen membranes. In a Cl(-)-containing medium, [3H]glutamate binding (Bmax=97.9 pmol/mg, Kd=349.68 nM) to this frozen CPM preparation was significantly displaced by excess quisqualic acid (QA) (65%), L-2-amino-4-phosphonobutyric acid (L-AP4) (35%), trans-1-aminocyclopentane-1,3-dicarboxylate (1S,3R-ACPD) (25%) and alfa-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) (25%). In a Cl(-)-free medium, binding (Bmax=44.14 pmol/mg, 311 nM) was significantly displaced by QA (45%), L-AP4 (25%), ACPD (25%), AMPA (25%), kainic acid (20%) and N-methyl-D-aspartate (15%).