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Rosh Ha'ayin, Israel

Williams N.M.,University of California at Davis | Winfree R.,Lipman
Biological Conservation | Year: 2013

Habitat loss from urban development threatens native plant populations in many regions of the world. In addition to direct plant mortality, urban intensification potentially impacts pollinator communities and in turn disrupts the pollination mutualisms that are critical to the viability of native plant populations. We placed standardized flowering plant arrays into woodlands along a gradient of increasing urban land use to simultaneously quantify landscape-scale and local-scale effects on pollinators and on reproduction of two spring ephemeral wildflowers (Claytonia virginica and Polemonium reptans) in woodland fragments in the Mid-Atlantic Region of North America. Greater pollinator abundance and associated diversity significantly reduced the degree of pollen limitation, demonstrating that pollinator populations are critical to successful pollination of these plant populations. However, landscape-scale habitat loss did not reduce pollinator abundance or diversity. Habitat loss at the landscape scale therefore does not appear to drive changes in pollination in this woodland system. Rather, local-scale habitat characteristics were more important, with pollinators being more abundant in brighter woodland patches for one plant species, and in larger patches for the other species. Because we found abundant pollinators and adequate pollination even in isolated, urban woodland fragments, our results are encouraging for the conservation of both plants and pollinators in urban landscapes. © 2013 Elsevier Ltd. Source

Bini E.,Lipman
FEMS Microbiology Ecology | Year: 2010

We are becoming increasingly aware of the role played by archaea in the biogeochemical cycling of the elements. Metabolism of metals is linked to fundamental metabolic functions, including nitrogen fixation, energy production, and cellular processes based on oxidoreductions. Comparative genomic analyses have shown that genes for metabolism, resistance, and detoxification of metals are widespread throughout the archaeal domain. Archaea share with other organisms strategies allowing them to utilize essential metals and maintain metal ions within a physiological range, although comparative proteomics show, in a few cases, preferences for specific genetic traits related to metals. A more in-depth understanding of the physiology of acidophilic archaea might lead to the development of new strategies for the bioremediation of metal-polluted sites and other applications, such as biomining. © 2010 Federation of European Microbiological Societies. Source

As part of a shift toward macromolecule production to support continuous cell proliferation, cancer cells coordinate the activation of lipid biosynthesis and the signaling networks that stimulate this process. A ubiquitous metabolic event in cancer is the constitutive activation of the fatty acid biosynthetic pathway, which produces saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) to sustain the increasing demand of new membrane phospholipids with appropriate acyl composition. In cancer cells, the tandem activation of the fatty acid biosynthetic enzymes adenosine triphosphate citrate lyase, acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) leads to increased synthesis of SFA and their further conversion into MUFA by stearoyl-CoA desaturase (SCD) 1. The roles of adenosine triphosphate citrate lyase, ACC and FAS in the pathogenesis of cancer have been a subject of extensive investigation. However, despite early experimental and epidemiological observations reporting elevated levels of MUFA in cancer cells and tissues, the involvement of SCD1 in the mechanisms of carcinogenesis remains surprisingly understudied. Over the past few years, a more detailed picture of the functional relevance of SCD1 in cell proliferation, survival and transformation to cancer has begun to emerge. The present review addresses the mounting evidence that argues for a key role of SCD1 in the coordination of the intertwined pathways of lipid biosynthesis, energy sensing and the transduction signals that influence mitogenesis and tumorigenesis, as well as the potential value of this enzyme as a target for novel pharmacological approaches in cancer interventions. © The Author 2010. Published by Oxford University Press. All rights reserved. Source

Waste grease lipids used in animal feeds have been the cause of food recalls in Europe, where such materials were incorporated into animal feedstuffs. This resulted in unwanted residues in human food. The composition of such lipid sources has been lacking. Seventeen composite trap grease and isolated brown grease samples were analyzed. Analytes included nutrients, metals, and volatile organic compounds. Analytes were selected for relevance to wastewater treatment and resource reuse potential. Moisture averaged 89.4% and the pH was 3.8. The 5-day biological oxygen demand was 32,531 mg/liter, solids were 7.5%, and fats, oil, and grease were 48,970 mg/liter. Non-polychlorinated biphenyl volatile organic compounds were surveyed. In the 17 grease samples, 14 contained an average of 102.5 μg/liter chloroform; 11 samples contained acetone, averaging 369 μg/liter; 9 samples contained 2- butanone, with an average of 484 μg/liter; and 8 contained an average of 710 μg/liter methylene chloride and toluene at 311 μg/liter. The mean concentration of copper in 17 composite samples ranged from 15 to 239 μg/liter, iron averaged 314 μg/liter, lead means ranged from 2.5 to 24 μg/liter, and magnesium averaged 975 μg/liter. It is hypothesized that food preparation facility cleaning and chlorinated cleaning-disinfection agents combined with the organics in the low-pH environment of the traps produce potentially carcinogenic compounds. It is recommended that these waste grease materials be used as a feedstock for biofuel. © International Association for Food Protection. Source

Epiophlebia diana sp.n. is described from larval specimens collected in the mountains of western Sichuan Province, China. Epiophlebian taxonomy, life history, and biogeography are reviewed, and keys provided for determination of the known adults and larvae of Epiophlebia Calvert, 1903. Classification of Epiophlebia is revised as follows: Epiophlebia s.str. with E. superstes (Selys, 1889) [type species] and E. sinensis Li & Nel, 2012; and Rheoepiophlebia subgen.n. with E. laidlawi Tillyard, 1921 [type species] and E. diana sp.n.. Behavioral, ecological and paleontological information is also evaluated and members of Epiophlebia acknowledged to have inhabited small high elevation streams of the east Palaearctic for possibly 180 million years. Likely reasons are proposed for the enduring survival of Epiophlebia, its lack of a fossil record and the extinction of related groups. © Senckenberg Gesellschaft für Naturforschung. Source

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