Absorption of acrylates and polysilazanes in the far UVC and the VUV regions

A simple but reliable method was developed for the determination of wavelength-dependent absorption coefficients in the vacuum-UV (VUV) spectral range 160 nm < λ < 195 nm.     

Some aspects on ruggedness of SiC power devices

This article is on effects that can destroy SiC power semiconductor devices. The failure physics in SiC devices are discussed based on the well understood effects in silicon devices. In some device properties, such as surge current, short circuit, static avalanche and dynamic avalanche, SiC has significant possible advantages compared to silicon. For cosmic ray stability, there are no unique results. Regarding thermal mechanical stress on interface materials, SiC is more challenging. The same may hold for electrical stress in passivation layers at the junction termination.     

Field classification of publications in Dimensions: a first case study testing its reliability and validity

Dimensions is a research data infrastructure and tool, including grants, publications, citations, clinical trials, and patents in one place. An interesting feature of Dimensions is its field classification scheme, which is not based on journal classification systems, as in the Web of Science or Scopus, but on machine learning. Each publication is assigned to at least one field. Using the set of my own publications, I investigated whether they were reliably and validly assigned to fields. The results put in question the reliability and validity of the scheme. Large scale studies seem necessary to investigate the scheme in more detail.

     

Book reviews

RESOURCE TRENDS AND POPULATION POLICY: A TIME FOR REASSESSMENT, by Lester R. Brown. Worldwatch Institute, Washington, D.C., May 1979; Worldwatch Paper 29. (Paperback $2.00)

THE NEXT SEVENTY YEARS: POPULATION, FOOD AND RESOURCES, by B. Gil‐land. Abacus Press, London, 1979. 133 pp. (£9.50)

POPULATION POLICY ANALYSIS, edited by M. E. Kraft and M. Schneider. D. C. Heath, London, 1979. (£0.00)

ENVIRONMENTAL IMPACT ASSESSMENT, by Brian B. Clark, Ronald Bisset and Peter Wath‐ern. Manssell, London and Bowker, New York, 1980. 516 pp. (£0.00)

ADVANCES IN ECOLOGICAL RESEARCH, Vol. 11, edited by Amyan MacFadyen. Academic Press, London, 1980. 428 pp. (£25.00)

MICROBIAL GROWTH AND SURVIVAL IN EXTREMES OF ENVIRONMENT, edited by G. W. Gould and Janet E. Cory. Academic Press, London, 1980. 244 pp. (£16.00)

UNDER NEW MANAGEMENT: Port Growth and Emerging Coastal Management Programs, by Marc Hershman, Robert Goodwin, Andrew Ruot‐sala, Maureen McCrea and Yehuda Hayuth. A Washington Sea Grant Publication, 1978. 212 pp. ($12.50)

HANDBOOK OF INDUSTRIAL ENERGY ANALYSIS, by J. Boustead and G. F. Hancock. Ellis‐Harwood, Chichester, U.K., 1979. (£25.00)

TREE GROWTH AND ENVIRONMENTAL STRESSES, by T. T. Kozlowski. University of Washington Press, Seattle and London, 1979. vii + 192 pp. (£12.50)

ALL GOOD THINGS AROUND US, by Pamela Michael. Illustrated by Christabel King. Ernest Benn Ltd., London, 1980. 240 pp. (£12.95)

HUMAN GEOGRAPHY (2nd Edition), by A. V. Perpillou. Longman Group, London, U.K., 1977. xviii + 570 pp. 37 pls., 27 maps and diagrams, Index. (Paperback £5.50)

INDUSTRIAL AND HAZARDOUS WASTES IMPOUNDMENT, by N. P. Cheremisinoff, P. N. Cheremisinoff, F. Ellerbeck and A. J. Perna. Ann Arbor Science, Michigan, 1979. ix + 475 pp. Index. (£16.25)

PHOSPHORUS IN THE ENVIRONMENT: ITS CHEMISTRY AND BIOCHEMISTRY. (Ciba Foundation No. 57, New Series), by Ruth Porter and David W. Fitzsimons. Elsevier, 1978. (£18.15)

TOXIC AND HAZARDOUS WASTE DISPOSAL. Vol. II, edited by R. B. Pojasek (Options for Sterilization Solidifications). Ann Arbor Science, Michigan, U.S.A., 1979, 259 pp. (£19.80)

SON OF THE WILDERNESS (The Life of John Muir), by Linnie Marsh Wolfe. The University of Wisconsin Press, Madison, 1978. 364 pp. (Paperback £4.90)

NATURE'S PRICE, by W. van Dieren and M. G. W. Hummelinck. Marion Boyars, London, Boston, 1979. (Paperback £3.50)

PERMACULTURE ONE, by Bill (B. C.) Molli‐son and David Holmgren. Corgi Books, Trans‐world Publishers Ltd., Melbourne, Australia. 128 pp. (A $4.95)

ENVIRONMENTAL AERODYNAMICS, by R. S. Scorer. Ellis Horwood, Chichester, U.K., 1978. 488 pp. (Hardback £20.00; paperback £7.50)     

Effectiveness of cationically modified cellulose polymers for dewatering algae

A method to flocculate algal cultures of Chlamydomonas reinhardtii using four different industrially produced polymers is presented. Starting with a 1 wt% stock polymer solution, flocculation times less than 60 min were observed for 0.1 to 0.6 g polymer per L of algae culture, while control samples took greater than 1400 min to flocculate. Cell counts showed that 99% of the cells were flocculated using the polymers compared to 73% for the control. Finally, the flocculation process was successful at both 5 and 40 mL batch sizes for one polymer; therefore, the method is efficient, effective and may be scalable.     

Contact dynamic modeling of a liquid droplet between two approaching porous materials

A computational fluid dynamics model based on a finite difference solution to mass and momentum conservation equations (Navier–Stokes equations) for a liquid droplet transport between two porous or nonporous contacting surfaces (CSs) is developed. The CS dynamic (equation of motion) and the spread of the incompressible liquid available on the primary surface for transfer are coupled with the Navier–Stokes equations. The topologies of the spread dynamic between and inside both surfaces (primary and CSs) are compared with experimental data. The amount of mass being transferred into the CS, predicted by the model, is also compared to the experimental measurements. The impact of the initial velocity on the spread topology and mass transfer into the pores is addressed. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2346–2353, 2014     

An Oral Male Courtship Pheromone Terminates the Response of Nasonia vitripennis Females to the Male-Produced Sex Attractant

Sex pheromones are crucial for mate finding in many animals. Long-range attraction, mate recognition, and the elicitation of sexual receptiveness during courtship are typically mediated by different compounds. It is widely unknown, however, how the different components of a species’ pheromone system influence each other. Here, we demonstrated in the parasitoid wasp Nasonia vitripennis that females quickly cease to respond to the male sex attractant after they contact a male’s oral secretion during courtship. We used this behavioral switch to monitor the fractionation of head extracts from male wasps for identification of the bioactive compounds as a blend of ethyl oleate, ethyl linoleate, and ethyl α-linolenate. This is the first identification of a cephalic courtship pheromone in parasitic Hymenoptera. Plasticity in pheromone-mediated sexual behavior of female insects has hitherto been attributed to the transfer of bioactive proteinaceous molecules with the male ejaculate. The pheromone interaction reported here sheds new light on the sexual communication of insects by showing that the sex pheromone response of females can be terminated by males independent of sperm transfer.     

ER Stress in ERp57 Knockout Knee Joint Chondrocytes Induces Osteoarthritic Cartilage Degradation and Osteophyte Formation

Ageing or obesity are risk factors for protein aggregation in the endoplasmic reticulum (ER) of chondrocytes. This condition is called ER stress and leads to induction of the unfolded protein response (UPR), which, depending on the stress level, restores normal cell function or initiates apoptotic cell death. Here the role of ER stress in knee osteoarthritis (OA) was evaluated. It was first tested in vitro and in vivo whether a knockout (KO) of the protein disulfide isomerase ERp57 in chondrocytes induces sufficient ER stress for such analyses. ER stress in ERp57 KO chondrocytes was confirmed by immunofluorescence, immunohistochemistry, and transmission electron microscopy. Knee joints of wildtype (WT) and cartilage-specific ERp57 KO mice (ERp57 cKO) were analyzed by indentation-type atomic force microscopy (IT-AFM), toluidine blue, and immunofluorescence/-histochemical staining. Apoptotic cell death was investigated by a TUNEL assay. Additionally, OA was induced via forced exercise on a treadmill. ER stress in chondrocytes resulted in a reduced compressive stiffness of knee cartilage. With ER stress, 18-month-old mice developed osteoarthritic cartilage degeneration with osteophyte formation in knee joints. These degenerative changes were preceded by apoptotic death in articular chondrocytes. Young mice were not susceptible to OA, even when subjected to forced exercise. This study demonstrates that ER stress induces the development of age-related knee osteoarthritis owing to a decreased protective function of the UPR in chondrocytes with increasing age, while apoptosis increases. Therefore, inhibition of ER stress appears to be an attractive therapeutic target for OA.     

The Deubiquitinase OTUB1 Is a Key Regulator of Energy Metabolism

Dysregulated energy metabolism is a major contributor to a multitude of pathologies, including obesity and diabetes. Understanding the regulation of metabolic homeostasis is of utmost importance for the identification of therapeutic targets for the treatment of metabolically driven diseases. We previously identified the deubiquitinase OTUB1 as substrate for the cellular oxygen sensor factor-inhibiting HIF (FIH) with regulatory effects on cellular energy metabolism, but the physiological relevance of OTUB1 is unclear. Here, we report that the induced global deletion of OTUB1 in adult mice (Otub1 iKO) elevated energy expenditure, reduced age-dependent body weight gain, facilitated blood glucose clearance and lowered basal plasma insulin levels. The respiratory exchange ratio was maintained, indicating an unaltered nutrient oxidation. In addition, Otub1 deletion in cells enhanced AKT activity, leading to a larger cell size, higher ATP levels and reduced AMPK phosphorylation. AKT is an integral part of insulin-mediated signaling and Otub1 iKO mice presented with increased AKT phosphorylation following acute insulin administration combined with insulin hypersensitivity. We conclude that OTUB1 is an important regulator of metabolic homeostasis.