Zwitterion‐Functionalized Detonation Nanodiamond with Superior Protein Repulsion and Colloidal Stability in Physiological Media

Nanodiamond (ND) is a versatile and promising material for bioapplications. Despite many efforts, agglomeration of nanodiamond and the nonspecific adsorption of proteins on the ND surface when exposed to biofluids remains a major obstacle for biomedical applications. Here, the functionalization of detonation nanodiamond with zwitterionic moieties in combination with tetraethylene glycol (TEG) moieties immobilized by click chemistry to improve the colloidal dispersion in physiological media with strong ion background and for the simultaneous prevention of nonspecific interactions with proteins is reported. Based on five building blocks, a series of ND conjugates is synthesized and their performance is compared in biofluids, such as fetal bovine serum (FBS) and Dulbecco's modified Eagle medium (DMEM). The adsorption of proteins is investigated via dynamic light scattering (DLS) and thermogravimetric analysis. The colloidal stability is tested with DLS monitoring over prolonged periods of time in various ratios of water/FBS/DMEM and at different pH values. The results show that zwitterions efficiently promote the anti‐fouling properties, whereas the TEG linker is essential for the enhanced colloidal stability of the particles.     

Interactivity Improves Usability of Geographic Maps for Visually Impaired People

Tactile relief maps are used by visually impaired people to acquire mental representation of space, but they retain important limitations (limited amount of information, braille text, etc.). Interactive maps may overcome these limitations. However, usability of these two types of maps has never been compared. It is then unknown whether interactive maps are equivalent or even better solutions than traditional raised-line maps. This study presents a comparison of usability of a classical raised-line map versus an interactive map composed of a multitouch screen, a raised-line overlay, and audio output. Both maps were tested by 24 blind participants. We measured usability as efficiency, effectiveness, and satisfaction. Our results show that replacing braille with simple audio-tactile interaction significantly improved efficiency and user satisfaction. Effectiveness was not related to the map type but depended on users’ characteristics as well as the category of assessed spatial knowledge. Long-term evaluation of acquired spatial information revealed that maps, whether interactive or not, are useful to build robust survey-type mental representations in blind users. Altogether, these results are encouraging as they show that interactive maps are a good solution for improving map exploration and cognitive mapping in visually impaired people.     

Multivariate Comparison of the Brabender Viscograph and the Rapid Visco Analyser Using Cross-linked Starch

The relation between two viscographs, the Brabender Viscograph and the Rapid Visco Analyser (RVA), has been determined by using multi-variate statistics. The viscographs determine the properties of cross-linked starch products by measuring a viscogram, i.e., the viscosity change during a well defined process of heating. With a Brabender viscograph it takes 50 min to measure the specifications of one sample, an RVA performs a similar temperature cycle in 10 min. The shorter measuring time should make the RVA more suited for process analysis than the Brabender Viscograph, provided that both viscograms give comparable information. A method is presented which establishes the correlation between the viscograms and predicts the Brabender characteristics from the RVA measurement. Viscograph measurements were performed with a set of 60 cross-linked potato starch products. The products were made by setting the levels of reagent, swelling inhibitor, reaction temperature and reaction time. The products were measured on both viscographs, each with its own optimized operating method. All four factors significantly affected the Brabender and RVA viscograms. Principal component analysis showed that the viscograms could be reduced to two principal components. The first principal component is the weighted mean viscosity, the second shows whether the peak viscosity is still present. The relation between Brabender and RVAwas analyzed with partial least squares. The analysis shows a strong correlation between both viscographs and the Brabender viscosities could be predicted from an RVA viscogram.     

Cycloaddition Reactions of 1,3‐Diaza‐2‐azoniaallene Salts and Glycals

The 1,3‐diaza‐2‐azoniaallene salt 3a reacts stereoselectively with glycals ( 5a—e ) to afford pyrano[2,3‐d]‐1,2,3‐ triazolium salts 6a—e . In contrast to other 1,3‐dipolar cycloadditions of glycals reported so far, the stereoselectivity of compounds 6 is not determined by the substituent on C‐3 of the glycal. Both cis ( 6a,b ) and trans ( 6d,e ) substitutions on C‐7 and C‐7a were found for bicyclic compounds 6 (crystal structure of 6a ). Under the influence of acid 6e opens the pyran ring to give the triazolium salt 9 . Addition of antimony pentachloride to a solution of the glycal 5e and the chlorotriazene 2a results in the formation of the pyranotriazene 12 containing two triazene units. In the presence of acid the pyranotriazene 6c reacts with alcohols to afford 2‐hydrazino glycosides 13a,b, 15 , which with zinc dust in acetic acid are reduced to 2‐amino glycosides 14a,b .     

The Influence of the Removal of Specific NOM Compounds by Anion Exchange on Ozone Demand,Disinfection Capacity,and Bromate Formation

This research on a pilot scale focuses on the reaction of ozone with natural organic matter (NOM) for three water qualities with different dissolved organic carbon (DOC) concentrations and NOM compositions, obtained after several stages of an anion exchange process. It was shown that for the same ozone dosage per DOC, the ozone demand was higher, less bromate was formed and a lower disinfection capacity was reached for water containing mainly humic substances, than for water where the humic substances were partly removed. It can be concluded that NOM composition, specifically the humic substances, influences the ozone demand, disinfection capacity and bromate formation.     

Intrusive memories in perpetrators of violent crime: Emotions and cognitions.

The authors investigated factors that may determine whether perpetrators of violent crime develop intrusive memories of their offense. Of 105 young offenders who were convicted of killing or seriously harming others, 46% reported distressing intrusive memories, and 6% had posttraumatic stress disorder. Intrusions were associated with lower antisocial beliefs before the assault, greater helplessness, fear, dissociation, data-driven processing and lack of self-referent processing during the assault, more disorganized assault narratives, and greater negative view of the self, negative interpretations of intrusive memories, perceived permanent change, and self-blame. In a logistic regression analysis, the cognitive and emotional variables explained substantial variance over and above demographic factors. The results suggest that cognitive factors that predict reexperiencing symptoms in victims of crime generalize to perpetrators. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Production of antibiotics by Collybia nivalis, Omphalotus olearis, a Favolaschia and a Pterula species on natural substrates

Collybia nivalis, Favolaschia sp. 87129, Pterula sp. 82168 and Omphalotus olearius were cultivated on natural substrates. The antibiotic metabolites oudemansin A. strobilurins A, D, illudin S and pterulone were isolated and identified. A new antifungal metabolite, pterulone B, was described from cultures of Pterula sp. 82168 on wood. Collybia nivalis was found to be the first species of this genus to produce strobilurins and oudemansin A. As compared to rich media the cultivation on natural substrates resulted in the production of fewer metabolites. The concentrations of the antibiotics, however, were sufficient to inhibit other saprophytic fungi.     

Comments on “Quasi-min-max MPC algorithm for LPV systems” by Y. Lu and Y. Arkun, Automatica 36 (2000) 527-540

This note shows that the solvability of the modified quasi-min-max MPC algorithm of the paper Lu and Arkun, Automatica 36 (2000) 527 for the systems with input constraints is not guaranteed and the proof of the theorems are not sufficient via a counterexample of the Remark 5.     

Modellierung für Integrated Enterprise Balancing

The development of models and methods is a vital element of design science in information systems research. In this paper a formal process modeling language is developed which incorporates IEB (Integrated Enterprise Balancing)/4R (Risk, Return, Regulation, Reporting) requirements formulated by Faisst and Buhl [FaBu05]. This is realized through the inclusion of 4R elements and 4R relations into the new 4R process modeling language. An evaluation of the process modeling language with regard to the assessment criterion “feasibility of implementation” was successfully executed using the meta modeling platform ADONIS. For that purpose the ADONIS modeling language for business processes (ADONIS BPMS) was extended with additional 4R modeling elements. Furthermore a new model type as well as required classes and relation classes have been developed which enable the connection of the 4R process modeling language to the research results of the above mentioned contribution.     

The influence of technical factors on differential cell count in milk

Differential cell count of milk is a traditional parameter for the evaluation of udder health. The literature shows great variation in differential cell counts of the milk of healthy mammary glands: macrophages range from 0% to 80%, lymphocytes from 1.5% to 79.5%, polymorphonuclear neutrophils from 3% to 95%, and epithelial cells from 1% to 19%. We conducted three studies to seek explanations for such variation. In the first, we evaluated the impact of polyethylene and glass sampling bottles. The aim of the second study was to compare the results of differential cell counts performed by three different technicians. The third study evaluated two methods of smear preparation. When polyethylene plastic bottles were used, the macrophage population was minimized but lymphocytes remained unaffected. This was shown by an exemplary flow cytometric analysis using four monoclonal antibodies against three lymphocyte surface structures. There were significant differences in the differential cell counts of 40 smears made by three technicians despite identical operating procedures. For the sediment smear, milk was centrifuged once and the sediment spread by eye on a glass slide. For the "coffee grinder" smear method, the sample was subjected to four centrifugations and then placed on a cover glass in order to spread the sediment using centrifugal force. The coffee grinder procedure led to a reduction of lymphocytes and an enrichment of polymorphonuclear neutrophils without affecting the macrophage population. Both methods made it possible to distinguish different udder health classes. It can be concluded that differential cell counts are a useful tool for comparing and monitoring udder health only if: samples are taken in a glass bottle; smears are prepared with the identical technique; and the differential cell counts are performed by a single person.