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991.
Jose M. Bonifacino 《Brittonia》2008,60(3):205-212
Nardophyllum armatum, a species from the Puna region of Argentina, Bolivia, and Chile is here transferred to genus Ocyroe, which in turn is resurrected from the synonymy under Nardophyllum. Ocyroe is characterized by thorny branches, discoid capitula, naked receptacles, glandular corollas with a globose swelling at the
base, and a profuse 3- to 5-seriate pappus. The new combination Ocyroe armata and a lectotype for Dolichogyne armata are here presented. 相似文献
992.
993.
Sawalha MF Peralta-Videa JR Duarte-Gardea M Gardea-Torresdey JL 《Bioresource technology》2008,99(10):4438-4444
Experiments performed on the Cu(II), Pb(II), and Zn(II) binding by saltbush biomass (Atriplex canescens) showed that the metal binding increased as pH increased from 2.0 to 5.0. The highest amounts of Cu, Pb, and Zn bound by the native biomass varied from 48-89%, 89-94%, and 65-73%, respectively. The hydrolyzed biomass bound similar amount of Pb and 50% more Cu and Zn than the native. The esterified biomass had a lower binding capacity than native; however, esterified flowers bound 45% more Cu at pH 2.0 than native flowers. The optimum binding time was 10 min or less. More than 60% of the bound Cu was recovered using 0.1 mM HCl, while more than 90% of Pb was recovered with either HCl or sodium citrate at 0.1 mM. For Zn, 0.1 mM sodium citrate allowed the recovery of 75%. Results indicated that carboxyl groups participate in the Cu, Pb, and Zn binding. 相似文献
994.
This work had the dual objective of selecting a substrate for rapid mycelial growth of Scytalidium thermophilum and then comparing the growth and production of a brown variety of Agaricus bisporus on substrate non-colonized and colonized with S. thermophilum. Mycelial growth of S. thermophilum at 45 degrees C was significantly greater on potato dextrose yeast extract agar (0.58 mm/h) as compared to malt extract glucose agar (0.24 mm/h) and yeast extract glucose agar (0.44 mm/h). On cereal grain, S. thermophilum grew significantly faster on rice (0.31 mm/h) compared to sorghum (0.22 mm/h) and millet (0.18 mm/h). It also grew faster on Pangola grass (0.49 mm/h) compared to corncobs (0.30 mm/h) and sawdust (0.18 mm/h). Colonization of Pangola grass with S. thermophilum was influenced by the addition of calcium salts in the form of gypsum, hydrated lime and ground limestone. For production of A. bisporus, biological efficiency (BE) on pasteurized Pangola grass pre-colonized by S. thermophilum for 4 days at 45 degrees C was more than twice (26.4%) that on grass non-colonized by S. thermophilum (11.0%). The addition of 2% hydrated lime to Pangola grass prior to colonization by S. thermophilum resulted in an additional doubling of BE of mushroom production (48.1%). These results show the possibility of developing a non-composted substrate method for producing A. bisporus without autoclaving the substrate. 相似文献
995.
Accelerated belowground C cycling in a managed agriforest ecosystem exposed to elevated carbon dioxide concentrations 总被引:2,自引:0,他引:2
We investigated the effects of three elevated atmospheric CO2 levels on a Populus deltoides plantation at Biosphere 2 Laboratory in Oracle Arizona. Stable isotopes of carbon have been used as tracers to separate the carbon present before the CO2 treatments started (old C), from that fixed after CO2 treatments began (new C). Tree growth at elevated [CO2] increased inputs to soil organic matter (SOM) by increasing the production of fine roots and accelerating the rate of root C turnover. However, soil carbon content decreased as [CO2] in the atmosphere increased and inputs of new C were not found in SOM. Consequently, the rates of soil respiration increased by 141% and 176% in the 800 and 1200 μL L?1 plantations, respectively, when compared with ambient [CO2] after 4 years of exposure. However, the increase in decomposition of old SOM (i.e. already present when CO2 treatments began) accounted for 72% and 69% of the increase in soil respiration seen under elevated [CO2]. This resulted in a net loss of soil C at a rate that was between 10 and 20 times faster at elevated [CO2] than at ambient conditions. The inability to retain new and old C in the soil may stem from the lack of stabilization of SOM, allowing for its rapid decomposition by soil heterotrophs. 相似文献
996.
Malgorzata Insińska-Rak Ewa Sikorska Jose R Herance Jose L Bourdelande Igor V Khmelinskii Maciej Kubicki Wies?aw Pruka?a Isabel F Machado Anna Komasa Luis F V Ferreira Marek Sikorski 《Photochemical & photobiological sciences》2005,4(6):463-468
Molecular structure, spectroscopic and photophysical data for the singlet state of 3-benzyl-lumiflavin in different solvents are presented. Theoretical studies concerning singlet-singlet and triplet-triplet excitation energies were carried out using time-dependent density functional theory (TD-DFT) calculations. These predictions are in good agreement with the experimental results, which reflect the solvent interactions. All the observable singlet-singlet transitions have pi-pi* character. The title compound appears to be an efficient sensitizer of the production of singlet oxygen (phi(Delta)= 0.53). The crystal structure of 3-benzyl-lumiflavin is also presented, along with its solid-state photophysical data. 相似文献
997.
998.
Marcio Carvalho de Moretzsohn Mark S Hopkins Sharon E Mitchell Stephen Kresovich Jose Francisco Montenegro Valls Marcio Elias Ferreira 《BMC plant biology》2004,4(1):11
Background
The genus Arachis is native to a region that includes Central Brazil and neighboring countries. Little is known about the genetic variability of the Brazilian cultivated peanut (Arachis hypogaea, genome AABB) germplasm collection at the DNA level. The understanding of the genetic diversity of cultivated and wild species of peanut (Arachis spp.) is essential to develop strategies of collection, conservation and use of the germplasm in variety development. The identity of the ancestor progenitor species of cultivated peanut has also been of great interest. Several species have been suggested as putative AA and BB genome donors to allotetraploid A. hypogaea. Microsatellite or SSR (Simple Sequence Repeat) markers are co-dominant, multiallelic, and highly polymorphic genetic markers, appropriate for genetic diversity studies. Microsatellite markers may also, to some extent, support phylogenetic inferences. Here we report the use of a set of microsatellite markers, including newly developed ones, for phylogenetic inferences and the analysis of genetic variation of accessions of A. hypogea and its wild relatives. 相似文献999.
Jennifer Soler Beatty Cristina Molnar Carlos M. Luque Jose F. de Celis María D. Martín-Bermudo 《PLoS genetics》2021,17(8)
Activation of Ras signaling occurs in ~30% of human cancers. However, activated Ras alone is insufficient to produce malignancy. Thus, it is imperative to identify those genes cooperating with activated Ras in driving tumoral growth. In this work, we have identified a novel EGFR inhibitor, which we have named EGFRAP, for EGFR adaptor protein. Elimination of EGFRAP potentiates activated Ras-induced overgrowth in the Drosophila wing imaginal disc. We show that EGFRAP interacts physically with the phosphorylated form of EGFR via its SH2 domain. EGFRAP is expressed at high levels in regions of maximal EGFR/Ras pathway activity, such as at the presumptive wing margin. In addition, EGFRAP expression is up-regulated in conditions of oncogenic EGFR/Ras activation. Normal and oncogenic EGFR/Ras-mediated upregulation of EGRAP levels depend on the Notch pathway. We also find that elimination of EGFRAP does not affect overall organogenesis or viability. However, simultaneous downregulation of EGFRAP and its ortholog PVRAP results in defects associated with increased EGFR function. Based on these results, we propose that EGFRAP is a new negative regulator of the EGFR/Ras pathway, which, while being required redundantly for normal morphogenesis, behaves as an important modulator of EGFR/Ras-driven tissue hyperplasia. We suggest that the ability of EGFRAP to functionally inhibit the EGFR pathway in oncogenic cells results from the activation of a feedback loop leading to increase EGFRAP expression. This could act as a surveillance mechanism to prevent excessive EGFR activity and uncontrolled cell growth. 相似文献
1000.
Juan L. Gutirrez‐Fisac Esther Lpez Jose R. Banegas Auxiliadora Graciani Fernando Rodríguez‐Artalejo 《Obesity (Silver Spring, Md.)》2004,12(4):710-715
Objective: To estimate the prevalence of obesity and overweight in the older adult population in Spain by sex, age, and educational level. Research Methods and Procedures: A cross‐sectional study was carried out in 2001 in a sample of 4009 persons representative of the noninstitutionalized population ≥60 years of age. Anthropometric measurements (BMI and waist circumference) were obtained using standardized techniques and equipment. Overweight was considered at a BMI of 25 to 29.9 kg/m2 and obesity at a BMI of ≥30 kg/m2. Central obesity was considered at a waist circumference of >102 cm in men and >88 cm in women. Results: The mean BMI was 28.2 kg/m2 in men and 29.3 kg/m2 in women. The prevalence of overweight and obesity in men was 49% and 31.5%, respectively. The corresponding percentages in women were 39.8% and 40.8%. The prevalence of obesity was higher in persons with no education than in those with third level education (i.e., university studies), especially among women (41.8% vs. 17.5%). The prevalence of central obesity was 48.4% in men and 78.4% in women. Differences by educational level were seen in only women, in whom the prevalence of central obesity was 80.9% in those with no education and 59% in those with third‐level education. Discussion: The prevalence of overweight and obesity in the Spanish adult elderly population is very high. Some other populations show similar prevalences, especially in Mediterranean countries. Socioeconomic conditions in Spain during the years these cohorts were born may partly explain the high‐frequency of obesity. 相似文献