Effects of the self-emission of an IR Fourier-transform spectrometer on measured absorption spectra

Up to now the effect of the modulated thermal self-emission of Fourier-transform spectrometers has been investigated for emission measurements only. But this instrumental radiation also influences Fourier-transform absorption spectroscopy in the mid-IR when the Moon, a hot blackbody, or even the Sun is taken as a radiation source, e.g., by causing small negative radiance values in the center of saturated absorption lines. For our experimental investigations, a blackbody that can be cooled down to liquid-nitrogen temperature was constructed. Measurements at different temperatures of the blackbody and for different optical configurations in the detector port of the Fourier spectrometer as well as transmission measurements of gas cells are used to examine the statements above.     

Nasal lavage as tool for health effect assessment of photochemical air pollution

In order to achieve esthetically more satisfying results, it has been proposed to place ITI implants with their border between the rough and smooth surfaces below the level of the alveolar crest, thereby obtaining a submucosally located implant shoulder following healing. The aim of the present experimental study was to clinically and radiographically evaluate the tissue response to the placement of one-stage transmucosal implants with the border between the rough and the smooth surfaces sunk by 1 mm into a subcrestal location. 11 patients underwent comprehensive dental care including the placement of 2 implants of the ITI Dental Implant System in the same quadrant (test and control). Randomly assigned control implants were placed according to the manufacturer's instructions, i.e. the border between the rough titanium plasma-sprayed and the smooth polished surfaces precisely at the alveolar crest. At the test implant the apical border of the polished surface was placed approximately 1 mm below the alveolar crest. Probing bone levels were assessed at implant placement (baseline), 4 and 12 months later. Modified plaque and modified gingival indices were recorded at 1, 2, 3, 4 and 12 months. Clinical probing depth and "attachment" levels were measured at 4 and 12 months. All parameters were assessed at 6 sites around each implant. The mean for each implant was calculated and used for analysis. The Wilcoxon matched pairs signed rank test and the Student t-test were applied to detect differences over time and between the test and control implants. At baseline, a mean difference in probing bone level of -0.86 mm (SD 0.43 mm, p < 0.05) was found between test and control implants with the test implants being placed more deeply. Both test and control implants lost a significant amount of clinical bone height during the first 4 months (test 1.16 mm, p < 0.05; control 0.58 mm, p < 0.05). However, only the test implants significantly lost clinical bone height from 4-12 months (test 1.04 mm, p < 0.05; control 0.45 mm, p = 0.08). Overall, the test implants lost 2.26 mm and the control implants 1.02 mm of bone height during the first year of service. On the average, the test implants demonstrated a bone level of 0.38 mm lower than the controls at 12 months. Except for the modified gingival index at 4 months (mean difference 0.21, SD 0.19, p < 0.05), no clinical parameters yielded significant differences between test and control implants at any time. It is concluded that in addition to the crestal bone resorption occurring at implants placed under standard conditions, the bone adjacent to the polished surface of more deeply placed ITI implants is also lost over time. From a biological point of view, the placement of the border between the rough and the smooth surfaces into a subcrestal location should not be recommended.     

Trial and error

A pac-learning algorithm isd-space bounded, if it stores at mostd examples from the sample at any time. We characterize thed-space learnable concept classes. For this purpose we introduce the compression parameter of a concept classb and design our Trial and Error Learning Algorithm. We show: b isd-space learnable if and only if the compression parameter ofb is at mostd. This learning algorithm does not produce a hypothesis consistent with the whole sample as previous approaches e.g. by Floyd, who presents consistent space bounded learning algorithms, but has to restrict herself to very special concept classes. On the other hand our algorithm needs large samples; the compression parameter appears as exponent in the sample size. We present several examples of polynomial time space bounded learnable concept classes:

- all intersection closed concept classes with finite VC-dimension.

- convexn-gons in ?².

- halfspaces in ?ⁿ.

- unions of triangles in ?².

We further relate the compression parameter to the VC-dimension, and discuss variants of this parameter.     

Analysis of Oligonucleotides by HPLC-Electrospray Ionization Mass Spectrometry

A new interface procedure has been developed that allows, for the first time, the high-efficiency analysis of synthetic oligonucleotides up to 75 bases by reversed-phase HPLC and on-line electrospray ionization mass spectrometry. For oligonucleotides up to 30 bases in length, single-base resolution can be obtained with low levels of cation adduct formation in the negative ion electrospray mass spectra. A key part of the method uses 1,1,1,3,3,3-hexafluoro-2-propanol as an additive to the HPLC mobile phase, adjusted to pH 7.0 with triethylamine. This novel additive results in both good HPLC separation and efficient electrospray ionization. The broad potential of this new method is demonstrated for synthetic homopolymers of thymidine (PolyT), fragments based on the pBR322 plasmid sequence, and phosphorothioate ester antisense oligonucleotides. This approach will be of particular utility for the characterization of DNA probes and PCR primers and quality control of antisense compounds such as phosphorothioates and their metabolites, as well as of materials used in clinical trials.     

Inhibitory effect of sulfur-containing amino acids on burnt off-flavours in canned liver sausages

The sensory quality of canned liver sausages is limited by a negative burnt high-temperature-heated flavour, caused by Maillard reaction products between amino acids and sugars. In experiments with liver sausage, reduced glutathione in concentrations of 0.01-0.30% had no positive effect on taste and color. N-acetyl-L-cysteine, an acylated derivative of the amino acid L-cysteine, was tested in concentrations between 0.03-0.50%; a concentration of 0.15% was optimal for the inhibition of the burnt flavour. An acid taste caused by lower pH was corrected by the addition of 0.25% diphosphate. When 0.15% N-acetyl-L-cysteine and 0.25% diphosphate were added to the sausage preparations, the heat-induced changes in amino acids and glucose were the same as in the control. Moreover, under different sterilization conditions, the additive mixture was shown to be an excellent inhibitor of the burnt flavour.     

A Review of Vertical Organic Transistors

Powerful electronic devices require performant short‐channel transistors. For organic electronics, though, promising low‐cost and flexible electronic circuits, high processing costs for short channel devices are not acceptable. In this regard, vertical organic transistors (VOTs) are an attractive alternative, and in fact, today they reach the highest transition frequency (40 MHz) and the highest footprint current density (>1 MA cm^?2) among all organic transistors. Here, all VOT concepts are reviewed, while discussing device physics, integration approaches, and highlighting the recent developments. The upcoming challenges for the VOT technology are also presented with a guideline for further developments.     

On the Impact of Using Utilities Rather than Costs for Graph Matching

The concept of graph edit distance constitutes one of the most flexible graph matching paradigms available. The major drawback of graph edit distance, viz. the exponential time complexity, has been recently overcome by means of a reformulation of the edit distance problem to a linear sum assignment problem. However, the substantial speed up of the matching is also accompanied by an approximation error on the distances. Major contribution of this paper is the introduction of a transformation process in order to convert the underlying cost model into a utility model. The benefit of this transformation is that it enables the integration of additional information in the assignment process. We empirically confirm the positive effects of this transformation on five benchmark graph sets with respect to the accuracy and run time of a distance based classifier.     

Identified research directions for using manufacturing knowledge earlier in the product life cycle

Design for manufacturing (DFM), especially the use of manufacturing knowledge to support design decisions, has received attention in the academic domain. However, industry practice has not been studied enough to provide solutions that are mature for industry. The current state of the art for DFM is often rule-based functionality within computer-aided design (CAD) systems that enforce specific design requirements. That rule-based functionality may or may not dynamically affect geometry definition. And, if rule-based functionality exists in the CAD system, it is typically a customisation on a case-by-case basis. Manufacturing knowledge is a phrase with vast meanings, which may include knowledge on the effects of material properties decisions, machine and process capabilities or understanding the unintended consequences of design decisions on manufacturing. One of the DFM questions to answer is: How can manufacturing knowledge, depending on its definition, be used earlier in the product life cycle to enable a more collaborative development environment? This paper will discuss the results of a workshop on manufacturing knowledge that highlights several research questions needing more study. This paper proposes recommendations for investigating the relationship of manufacturing knowledge with shape, behaviour and context characteristics of a product to produce a better understanding of what knowledge is most important. In addition, the proposal includes recommendations for investigating the system-level barriers to reusing manufacturing knowledge and how model-based manufacturing may ease the burden of knowledge sharing. Lastly, the proposal addresses the direction of future research for holistic solutions of using manufacturing knowledge earlier in the product life cycle.     

Responses of Microcrustaceans to Simulated Microgravity (2D-Clinorotation) - Preliminary Assessments for the Development of Bioregenerative Life Support Systems (BLSS)

Bioregenerative Life Support Systems (BLSS) are an endeavor to create environments able to maintain human life e.g. on future long-duration space missions like flights to Mars. Based on cyclic biological processes, these systems will be independent from material resupply (such as food, water and oxygen). Due to their central role in limnic ecosystems, herbivorous microcrustaceans could act as key player in aquatic BLSS as they link oxygen liberating, autotrophic producers like algae to higher trophic levels, such as fish. However, before such BLSS can be utilized in space, organisms inhabiting these systems have to be studied thoroughly to disclose the gravitational impact on the biological processes. This is possible in real microgravity, but requires high financial resources, is opportunity-limited or periods of microgravity are very short. Yet, cost-effective and almost permanently accessible tools for gravitational research are ground-based facilities (GBFs), providing simulated microgravity. Among those GBFs is the so called 2D-clinostat. In the present study we demonstrate, that rotation of clinostat tubes does not generate acceleration in form of (predator resembling) small scale turbulence, which can be perceived by Daphnia cucullata. Additionally, embryonal development is not disturbed in subitaneous eggs of Daphnia magna and resting eggs of the ostracod Heterocypris incongruens (besides through restrictions in space within the narrow clinostat tubes), just as subsequent hatching from the respective eggs. Hence, our results indicate that clinorotation is a suitable method to simulate microgravity for microcrustaceans.     

Efficiency enhancement of InP‐based inverted QD‐LEDs by incorporation of a polyethylenimine modified Al:ZnO layer

We report efficiency enhancement of indium phosphide (InP) quantum dot‐based light‐emitting diodes (QD‐LEDs) by using an polyethylenimine (PEI) surface modifier. By adapting a solution processed PEI layer on top of a aluminum doped zinc oxide (Al:ZnO) nanoparticle (NP) film, the leakage current of the inverted device was substantially suppressed. In addition, the electron injection into the conduction band edge (CBE) of InP/ZnSe/ZnS QDs was also facilitated by the low work function (WF) of the Al:ZnO film which was realized by the strong interfacial dipoles of the thin film of PEI. As a result, the charge balance in the inverted devices was controlled by the change of surface roughness, the WF and the thickness of neighboring layers via spin‐coating the PEI dissolved in alcohol mixture on the Al:ZnO layer such that the current efficiency was dramatically increased from 0.07 cd/A to 3.17 cd/A. The performance of our device is not comparable to Cd‐based devices; however, it shows the great potential for using an interfacial dipole layer to develop highly efficient InP‐based inverted QD‐LEDs.