Fecundity limits in Frangula alnus (Rhamnaceae) relict populations at the species' southern range margin

The geographic range of many temperate plant species is constrained by climate, but it remains little known how climate affects population performance at low-latitude range margins. This study investigated the reproduction of the Eurasian tree Frangula alnus in relict populations near its southwestern range limit in southern Spain. The aim was to identify the principal stages and causes of ovule loss experienced by these marginal populations. More than 6,800 flowers were monitored over 2 years, insect observations and different experiments were carried out to assess levels of pollen and resource limitation, as well as the influence of flowering phenology on seed production. Most ovule losses occurred during flower anthesis and were due to strong cross-pollen limitation. Fruit set was affected by tree size, light regime and flowering phenology, probably through their effects on pollinator behaviour. Fruit set was almost zero throughout the first half of the flowering season. Then it increased paralleling changes in pollinator abundance but was soon overridden by increasing ovule desiccation due to summer drought. Successful seed production was mostly confined to a brief period near the end of the flowering season. Adverse weather during this period in the second study year resulted in a threefold bud and flower mortality and a 50% decrease of fruit production. Spring rainfalls in southwestern Spain have diminished more than 30% through past decades leading to an earlier onset of summer drought. This trend and its adverse effects on seed production may contribute to explaining the recent decline of F. alnus at its southwestern range limit. © Springer-Verlag 2005.Peer Reviewe

Analysis of reasons of insufficient wear resistance of pumps waterjet mixes

Проведен анализ недостаточной износостойкости деталей насосов для гидроабразивных смесей. Предложены пути повышения износостойкости деталей проточной части насосов на основе применения штампованных деталей взамен литых, а также композиционных материалов на основе углерод‐углерода.The analysis of the lack of wear parts pumps waterjet mixtures. Ways of improving the durability of the parts flow pump through the use of forged parts to replace the cast, as well as composite materials based on carbon‐carbon

Frequent expression loss of Inter-alpha-trypsin inhibitor heavy chain (ITIH) genes in multiple human solid tumors: A systematic expression analysis

<p>Abstract</p> <p>Background</p> <p>The inter-alpha-trypsin inhibitors (ITI) are a family of plasma protease inhibitors, assembled from a light chain – bikunin, encoded by <it>AMBP </it>– and five homologous heavy chains (encoded by <it>ITIH1</it>, <it>ITIH2</it>, <it>ITIH3</it>, <it>ITIH4</it>, and <it>ITIH5</it>), contributing to extracellular matrix stability by covalent linkage to hyaluronan. So far, ITIH molecules have been shown to play a particularly important role in inflammation and carcinogenesis.</p> <p>Methods</p> <p>We systematically investigated differential gene expression of the <it>ITIH </it>gene family, as well as <it>AMBP </it>and the interacting partner <it>TNFAIP6 </it>in 13 different human tumor entities (of breast, endometrium, ovary, cervix, stomach, small intestine, colon, rectum, lung, thyroid, prostate, kidney, and pancreas) using cDNA dot blot analysis (Cancer Profiling Array, CPA), semiquantitative RT-PCR and immunohistochemistry.</p> <p>Results</p> <p>We found that <it>ITIH </it>genes are clearly downregulated in multiple human solid tumors, including breast, colon and lung cancer. Thus, <it>ITIH </it>genes may represent a family of putative tumor suppressor genes that should be analyzed in greater detail in the future. For an initial detailed analysis we chose <it>ITIH2 </it>expression in human breast cancer. Loss of <it>ITIH2 </it>expression in 70% of cases (n = 50, CPA) could be confirmed by real-time PCR in an additional set of breast cancers (n = 36). Next we studied ITIH2 expression on the protein level by analyzing a comprehensive tissue micro array including 185 invasive breast cancer specimens. We found a strong correlation (p < 0.001) between ITIH2 expression and estrogen receptor (ER) expression indicating that ER may be involved in the regulation of this ECM molecule.</p> <p>Conclusion</p> <p>Altogether, this is the first systematic analysis on the differential expression of <it>ITIH </it>genes in human cancer, showing frequent downregulation that may be associated with initiation and/or progression of these malignancies.</p