Laminated glass tubes as structural units in architecture and civil engineering

Α new type of large-sized glass tubes has been developed by laminating a load bearing inner core tube with protecting and supporting outer half shells. Additionally, for high loads to be transferred, the eontaet zone between glass and support material has been studied. The result is - contrary to common judgment - that in this ease the permissible stretching strain of the support material should be higher than the compressive stress to be transferred. In this way laminated glass tubes meet the essential requirements of architecture and civil engineering by: - tolerating high compressive stress (up to 60 MPa) without any failure, - maintaining high residual strength under load even after serious damage. It is hoped that the structural suitability of glass will be noticed by technicians and that this will succeed in reducing the reservations that still exist vis-a-vis this attractive, high-calibrated material. It gives not just architects, but civil engineers, interior designers, lighting specialists and others a new perspective, enabling them to design and build more transparent, more elegant and hopefully lighter-weight structures

Single Cell Kinetics of Phenotypic Switching in the Arabinose Utilization System of E. coli

Inducible switching between phenotypes is a common strategy of bacteria to adapt to fluctuating environments. Here, we analyze the switching kinetics of a paradigmatic inducible system, the arabinose utilization system in E. coli. Using time-lapse fluorescence microscopy of microcolonies in a microfluidic chamber, which permits sudden up-and down-shifts in the inducer arabinose, we characterize the single-cell gene expression dynamics of the araBAD operon responsible for arabinose degradation. While there is significant, inducer-dependent cell-to-cell variation in the timing of the on-switching, the off-switching triggered by sudden removal of arabinose is homogeneous and rapid. We find that rapid off-switching does not depend on internal arabinose degradation. Because the system is regulated via the internal arabinose level sensed by AraC, internal arabinose must be rapidly depleted by leakage or export from the cell, or by degradation via a non-canonical pathway. We explored whether the poorly characterized membrane protein AraJ, which is part of the arabinose regulon and has been annotated as a possible arabinose efflux protein, is responsible for rapid depletion. However, we find that AraJ is not essential for rapid switching to the off-state. We develop a mathematical model for the arabinose system, which quantitatively describes both the heterogeneous on-switching and the homogeneous off-switching. The model also predicts that mutations which disrupt the positive feedback of internal arabinose on the production of arabinose uptake proteins change the heterogeneous on-switching behavior into a homogeneous, graded response. We construct such a mutant and confirm the graded response experimentally. Taken together, our results indicate that the physiological switching behavior of this sugar utilization system is asymmetric, such that off-switching is always rapid and homogeneous, while on-switching is slow and heterogeneously timed at sub-saturating inducer levels

Synthesis of cyclopropyl-substituted furans by Brønsted acid promoted cascade reactions

Chloroacetic acid promotes an efficient and diastereoselective intramolecular cascade reaction of electron-deficient ynenones to deliver products featuring a 2,3,5-trisubstituted furan bearing a fused cyclopropyl substituent at the 5-position. Synthetically relevant polycyclic building blocks featuring rings of various sizes and heteroatoms have been synthesized in high yield using this mild acid-catalyzed reaction

Prediction of Cancer Incidence and Mortality in Korea, 2011

PURPOSE: To estimate the current cancer burden in Korea, cancer incidence and mortality were projected for the year 2011. MATERIALS AND METHODS: The cancer incidence data from 1999-2008 were obtained from the Korea National Cancer Incidence Database, and the cancer mortality data from 1993-2009 were obtained from the Korea National Statistics Office. Cancer incident cases and rates in 2011 were projected from fitting a linear regression model on observed age-specific cancer incidence rates against observed years, then multiplying the projected age-specific rates by the age-specific population. For cancer mortality, a similar procedure was applied for projection except that a Joinpoint regression model was used to determine at which year the linear trend significantly changed. RESULTS: A total of 216,809 new cancer cases and 71,036 cancer deaths are projected to occur in Korea in 2011. For all sites combined, the crude incidence rates are projected to be 437.9 and 420.5 and the age-standardized incidence rates are projected to be 336.5 and 279.7 per 100,000 for men and women, respectively. CONCLUSION: Cancer has become an important public health concern in Korea, and as Korea becomes an aged society, the cancer burden will continue to increase.ope

The global exposure of species ranges and protected areas to forest management

Aim Many vertebrate species globally are dependent on forests, most of which require active protection to safeguard global biodiversity. Forests, however, are increasingly either being disturbed, planted or managed in the form of timber or food plantations. Because of a lack of spatial data, forest management has commonly been ignored in previous conservation assessments. Location Global. Methods We combine a new global map of forest management types created solely from remote sensing imagery with spatially explicit information on the distribution of forest-associated vertebrate species and protected areas globally. Using Bayesian logistic regressions, we explore whether the amount of forested habitat available to a species as well as information on species-specific threats can explain differences in IUCN extinction risk categories. Results We show that disturbed and human-managed forests dominate the distributional ranges of most forest-associated species. Species considered as non-threatened had on average larger amounts of non-managed forests within their range. A greater amount of planted forests did not decrease the probability of species being threatened by extinction. Even more worrying, protected areas are increasingly being established in areas dominated by disturbed forests. Conclusion Our results imply that species extinction risk and habitat assessments might have been overly optimistic with forest management practices being largely ignored so far. With forest restoration being at the centre of climate and conservation policies in this decade, we caution that policy makers should explicitly consider forest management in global and regional assessments

Cancer Statistics in Korea: Incidence, Mortality and Survival in 2005

Cancer has been the most common cause of death in Korea since 1983 and is a major public health concern. This paper overviews the nationwide cancer statistics, including incidence, mortality, and survival rates, and their trends in Korea. In 2005, 142,610 new cancer cases and 65,117 cancer deaths occurred in Korea. The incidence rate for all cancer combined increased by 2.6% annually from 1999 to 2005. Significant increases have occurred in the incidence of colorectal, thyroid, female breast, and prostate cancers. The number of cancer deaths has increased over the past two decades, due mostly to population aging, while the age-standardized mortality rates have decreased in both men and women since 2002. Notable improvement has been observed in the 5-yr relative survival rates for most major cancers and for all cancer combined, with the exception of pancreatic cancer. The nationwide cancer statistics in this paper will provide essential data for evidence-based decisions in the national cancer control program in Korea