Irradiation as a method for decontaminating food. A review

In the present work we report the high-level expression of foreign genes encoding the light-harvesting (LHII) membrane-spanning polypeptides in photosynthetic bacteria. To do this we first constructed three deletion strains of Rhodovulum (Rhv.) sulfidophilum in which all or part of the puc operon, encoding the peripheral light-harvesting proteins, is missing. To investigate the heterologous expression of the light-harvesting polypeptides from Rb. capsulatus in Rhv. sulfidophilum and vice versa we have reintroduced functional foreign LH genes into these and equivalent strains of Rhodobacter (Rb.) capsulatus. In some cases very high levels of expression were obtained (85%) of those observed in the wild type), while in other cases much lower expression was observed; possible reasons for these differences are discussed. The heterologously expressed proteins were shown to contain normal pigment-binding sites and to be normally and functionally integrated within the host photosynthetic apparatus. The results indicate that heterologous proteins are able to assemble properly and enter into the same protein-protein interactions as their analogs originally present in the host strain.     

News

This section of Scientometrics will carry fresh and reliable news of people, programs, recent and forthcoming meetings and publications etc. Its effectiveness depends greatly on your assistance. Items for inclusion should be submitted to the Section Editor, Dr. J. Farkas.     

An improved method using respirography for the design of activated sludge aeration systems

For the computation of the oxygen uptake for the aeration tank of the biological treatment plant several methods are available such as the OC/L method, Emde's method with fixed coefficients, Eckenfelder's method, and the method of levels of dissolved oxygen. The method for the determination of oxygen uptake for the treatment of industrial wastewaters was developed. The advantage of this method is a simple calculation of oxygen uptake for industrial biological treatment plant due to independent measurement of oxygen uptake for individual phases. The method is rapid and allows easy determination of individual phases of oxygen uptake.     

Sanity examiner certification: An evolving national agenda.

A national survey of the states and territories revealed that the vast majority of state courts allow psychologists (and other nonphysician health care providers) to serve as forensic experts. Over the past decade organized psychology has been similarly successful in removing all known legislative and administrative barriers to its participation in the federal judicial system. The American Bar Association's criminal justice mental health standards provide for parity with medicine. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comments on Levin et al. and Rosen and Kopel: Internal and external validity issues.

Discusses problems of internal and external validity relevant to applied laboratory research in the modification of sexual behaviors. Two case studies presented by S. M. Levin et al (see record 1978-01505-001) and R. C. Rosen and S. A. Kopel (see record 1978-01511-001) are used to illustrate these problems. Suggestions are presented for improving the internal validity and the generalizability of studies using the laboratory paradigm. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interstitial cystitis in adolescent girls

Two cases of interstitial cystitis with typical, large bladder ulcerations in adolescent girls are reported. The specific diagnosis was confirmed histologically after full-thickness segmental resection of the bladder wall at the site of the ulceration during subsequent operations. Contrary to other reports based on subjective clinical findings, interstitial cystitis in children is rare when rigid criteria, including careful histological study, are applied. Treatment in children is the same as in adults and should be conservative. A conscientious attempt should be made to exclude infection and tuberculosis as possible contributors to the symptoms of urinary frequency and discomfort, as well as other causes of bladder abnormality. If conservative management fails to relieve symptoms the bladder may be enlarged in some cases by using a segment of intestine.     

Post-mortem study of the hip joint. III. Correlations between observations

Correlations between alterations in hip joints, described in a post-mortem study, have established the independence of limited and progressive alterations, and in addition have shown that there is a weak association between limited alterations and osteophytes and a strong one between progressive alterations and osteophytes. Nevertheless limited alterations may rarely undergo progressive damage. Cysts relate strongly to osteophytes but only moderately with progressive alterations. Limited alterations of both head and acetabulum can be subdivided. Some implications of these findings are discussed.     

High-voltage SPM oxidation of ZrN: materials for multiscale applications

Scanning probe microscope (SPM) oxidation was used to form zirconium oxide features on 200?nm thick ZrN films. The features exhibit rapid yet controlled growth kinetics, even in contact mode with 70?V dc applied between the probe tip and substrate. The features grown for times longer than 10?s are higher than 200?nm, and reach more than 1000?nm in height after 300?s. Long-time oxidation experiments and selective etching of the oxides and nitrides lead us to propose that as the oxidation reaches the silicon substrate, delamination occurs with the simultaneous formation of a thin layer of new material at the ZrN/Si interface. High-voltage oxide growth on ZrN is fast and sustainable, and the robust oxide features are promising candidates for multiscale (nanometre-to-micrometre) applications.     

Improving the ductility of nanocrystalline bcc metals

Nanocrystalline metals present extremely high yield strengths but limited ductility. Using atomistic simulations, we show that the fracture resistance of bcc nanocrystalline materials increases with decreasing grain size below a critical grain size. There appears to be a "most brittle" grain size corresponding to the "strongest size" that has been postulated. Impurities that strengthen the grain boundaries can improve ductility significantly for the relatively larger grain sizes, whereas ductility decreases for the smallest grain sizes.