bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetic Study of Singlet-Oxygen Quenching by Caffeic Acid and Related Phenols
Authors: Ohara Keishi , Ichimura Yoko , Nagaoka Shin-ichi 
Published: June 2009

Abstract
The second-order rate constants (kQ) of singlet-oxygen quenching by caffeic acid and related phenols were measured in ethanol and toluene. Caffeic acid derivatives deactivate singlet-oxygen largely by physical quenching at kQ = 106–107 M−1 s−1 through the charge-transfer transition state.
Three-Dimensional Morphological Chirality Induction in Polythiophene Polymer Deposit Using a Magnetic Field
Authors: Tanimoto Yoshifumi , Shinyama Ami , Omote Kanako 
Published: June 2009

Abstract
Effects of a vertical magnetic field on the three-dimensional morphology of a polythiophene deposit formed by anodic oxidation were examined. At 4 T, a left-handedly twisted polymer deposit is obtained, although the shape is uncurved in a zero field. The twist configuration is right-handed when the field direction is reversed. The mechanism of magnetic field effects is discussed.
High-Resolution Solid-State NMR Studies of Natural Abundant 15N Observed in Halogen-Bridged One-Dimensional Complexes, [NiX(chxn)2]X2 and [Pd(chxn)2][PdX2(chxn)2]Y4 (chxn = (1R,2R)-Diaminocyclohexane; Y = X (Halogen), NO3, and ClO4)
Authors: Kimura Noriyoshi , Shimizu Tadashi , Ikeda Ryuichi 
Published: June 2009

Abstract
We performed solid-state NMR measurements of 15N nuclei with a low natural abundance in chxn ligands in halogen-bridged Pd and Ni complexes with a one-dimensional (1-D) structure. Spectra obtained for 15N bonded to Pd2+, Pd4+, and Ni3+ were clearly separated from each other, and it was shown that information on electronic and magnetic structures of 1-D chains was obtained more sensitively than from 13C NMR data. A characteristic new result is a marked broadening of the signal from nitrogen bonded to the Pd4+ in [Pd(chxn)2][PdBr2(chxn)2]Br4, which is expected to be closely connected with polarons formed on 1-D chains.
1H and 27Al NMR Study of Li[AlH4] + Ti Compounds in Solution
Authors: Takeuchi Shou , Senoh Hiroshi , Zhang Shu , Takeshita Hiroyuki T , Kiyobayashi Tetsu , Xu Qiang , Kuriyama Nobuhiro 
Published: June 2009

Abstract
A broad sextet signal in the 1H NMR spectrum of Li[AlH4] in THF-d8, centered at 2.75 ppm with J/Hz = 176, was assigned to the signal from [AlH4]−. Also investigated were the reactions of Li[AlH4] with TiCl3 or Ti(OBu)4 in THF.
How Are Non-Bonded G···Z (Z = O, S, and Se) Distances at Benzene 1,2-, Naphthalene 1,8-, and Anthracene 1,8,9-Positions Controlled? An Approach to Causality in Weak Interactions
Authors: Hayashi Satoko , Nakanishi Waro 
Published: June 2009

Abstract
Mechanisms operating in weak interactions are sometimes quite different from those in strong ones. Factors to control the non-bonded G···Z (Z = O, S, and Se) distances at naphthalene 1,8-positions in 8-G-1-RZC10H6 are analyzed as an example to clarify the causality of weak interactions. Structures around Z in 8-G-1-RZC10H6 are well explained by three types, A, B, and C, where the Z–CR bond is perpendicular to the naphthyl plane in A, it is placed on the plane in B, and C is intermediate between A and B. The r(Z···Z) distances in 1,8-(RZ)2C10H6 are observed to increase in an order of BB &lt; CC &lt; AB &lt; AA. It seems difficult to explain the sequence based on the magnitudes of the closed-shell Z···Z interactions, since the BB interaction must not be so strong especially for Z of heavier atoms. The mechanism to control the r(Z···Z) distances is demonstrated to be the reflection from the repulsive interactions between R and H at the 2-position in 1,8-(RZ)2C10H6. Similar phenomena are also detected in the observed and calculated results at the benzene 1,2-, anthracene 1,8,9-, and anthraquinone 1,8,9-positions, which are explained based on the mechanism. Proposed idea and mechanism will help us to understand what happens in such weak interactions.
Synthesis and Structural Analysis of Triphenylmethane-Based Alkanecarboxamides and Their Assembly into Nanometer-Size Fibrous Objects
Authors: Houjou Hirohiko , Koga Tatsuya , Akiizumi Midori , Yoshikawa Isao , Araki Koji 
Published: June 2009

Abstract
A series of C3-symmetric trialkanecarboxamido derivatives was synthesized via a triphenylmethane derivative. The triamides with short alkyl chains (1–6 carbons) crystallized as either prisms or plates, whereas those with long alkyl chains (7–11 carbons) formed gel-like objects composed of fibrous crystals with 100-nm diameters. A discontinuity as a function of alkyl chain length was also observed for the melting points, the vibrational frequencies of the amide groups, and the powder X-ray diffraction patterns of the triamides. On the basis of analysis of the crystal structures of two of the compounds, we make some proposals about the molecular packing and the local structure of the molecular assembly. Our results suggest that there were critical differences in inter-core interactions and in the hydrogen-bonding network, depending on the length of the alkyl chains. We interpret the drastic change in morphology brought about by the tuning of the chain length as a consequence of a change in the mode of molecular assembly.
PCR-Based Methods for Detecting Single-Locus DNA Methylation Biomarkers in Cancer Diagnostics, Prognostics, and Response to Treatment
Authors: Kristensen Lasse Sommer , Hansen Lise Lotte 
Published: June 2009

AbstractBackground: DNA methylation is a highly characterized epigenetic modification of the human genome that is implicated in cancer. The altered DNA methylation patterns found in cancer cells include not only global hypomethylation but also discrete hypermethylation of specific genes. In particular, numerous tumor suppressor genes undergo epigenetic silencing because of hypermethylated promoter regions. Some of these genes are considered promising DNA methylation biomarkers for early cancer diagnostics, and some have been shown to be valuable for predicting prognosis or the response to therapy.Content: PCR-based methods that use sodium bisulfite–treated DNA as a template are generally accepted as the most analytically sensitive and specific techniques for analyzing DNA methylation at single loci. A number of new methods, such as methylation-specific fluorescent amplicon generation (MS-FLAG), methylation-sensitive high-resolution melting (MS-HRM), and sensitive melting analysis after real-time methylation-specific PCR (SMART-MSP), now complement the traditional PCR-based methods and promise to be valuable diagnostic tools. In particular, the HRM technique shows great potential as a diagnostic tool because of its closed-tube format and cost-effectiveness.Summary: Numerous traditional and new PCR-based methods have been developed for detecting DNA methylation at single loci. All have characteristic advantages and disadvantages, particularly with regard to use in clinical settings.
Screening Panels for Detection of Monoclonal Gammopathies
Authors: Katzmann Jerry A , Kyle Robert A , Benson Joanne , Larson Dirk R , Snyder Melissa R , Lust John A , Rajkumar S Vincent , Dispenzieri Angela 
Published: June 2009

Abstract
Background: The repertoire of serologic tests for identifying a monoclonal gammopathy includes serum and urine protein electrophoresis (PEL), serum and urine immunofixation electrophoresis (IFE), and quantitative serum free light chain (FLC). Although there are several reports on the relative diagnostic contribution of these assays, none has looked at the tests singly and in combination for the various plasma cell proliferative disorders (PCPDs).
Methods: Patients with a PCPD and all 5 assays performed within 30 days of diagnosis were included (n = 1877). The diagnoses were multiple myeloma (MM) (n = 467), smoldering multiple myeloma (SMM) (n = 191), monoclonal gammopathy of undetermined significance (MGUS) (n = 524), plasmacytoma (n = 29), extramedullary plasmacytoma (n = 10), Waldenström macroglobulinemia (WM) (n = 26), primary amyloidosis (AL) (n = 581), light chain deposition disease (LCDD) (n = 18), and POEMS syndrome (n = 31).
Results: Of the 1877 patients, 26 were negative in all assays. Omitting urine from the panel lost an additional 23 patients (15 MGUS, 6 AL, 1 plasmacytoma, 1 LCDD), whereas the omission of FLC lost 30 patients (6 MM, 23 AL, and 1 LCDD). The omission of serum IFE as well as urine lost an additional 58 patients (44 MGUS, 7 POEMS, 5 AL, 1 SMM, and 1 plasmacytoma).
Conclusions: The major impact of using a simplified screening panel of serum PEL plus FLC rather than PEL, IFE, and FLC is an 8% reduction in sensitivity for MGUS, 23% for POEMS (7 patients), 4% for plasmacytoma (1 patient), 1% for AL, and 0.5% for SMM. There is no diminution in sensitivity for detecting MM, macroglobulinemia, and LCDD.
Seasonal Changes in Carbohydrate and Nitrogen Concentrations in Oregon and California Populations of Brazilian Egeria (Egeria densa)
Authors: Pennington Toni G. , Sytsma Mark D. 
Published: June 2009

AbstractTotal nonstructural carbohydrate (TNC) reserves support growth, formation of reproductive structures, and sprouting of plant tissues, and nitrogen (N) is essential for amino acid synthesis and photosynthetic enzyme production. Timing of weed management to periods when these critical resources are most limiting might improve efficacy. We examined seasonal changes in carbohydrate and nitrogen concentrations in Brazilian egeria (Egeria densa), a common submersed aquatic weed, from two locations in the United States. Plants were collected from a coastal Oregon reservoir and from California's Central Valley in the Sacramento–San Joaquin Delta. Starch comprised between 35 to 51% of the TNC in lower stems and root crowns. Seasonal changes in resource concentrations were not consistent between years within a population or for the same plant part between different populations. Lowest TNC concentrations were observed earlier in the growing season (March) in Disappointment Slough than in Big Creek (May to June). Conversely, highest concentrations were observed in October in Disappointment Sough and from August to March in Big Creek. Nitrogen concentrations were highest in stem tips in both populations, with more distinct seasonal changes in the California population. These data suggest western populations of E. densa might exhibit less-discernible low points in root crown and lower stem energy storage for targeting management activities to vulnerable phenological stages. Brazilian egeria has high phenological plasticity despite its low genetic diversity and lack of specialized reproductive and perennating structures, which allows the plant to invade and dominate submersed plant communities in areas with mild winters.
Functional Group Responses to Reciprocal Plant Litter Exchanges between Native and Invasive Plant Dominated Grasslands
Authors: Sheley Roger , Vasquez Edward , Hoopes Carla 
Published: June 2009

AbstractManipulating plant litter to direct successional trajectories is rarely considered as a management strategy. Our objective was to determine the influence of litter from an intact native plant community on a community dominated by an invasive species within the same habitat type as well as the influence of litter from a community dominated by an invasive species on an intact native plant community. We hypothesized that litter amount, type (source), and fragment size would influence various functional groups within a native plant community differently than within a weed-dominated plant community. We used reciprocal plant litter exchanges between native and invasive plant–dominated grasslands to gain an initial understanding of litter's influence on the density and biomass of native grasses, native forbs, common St. Johnswort, and downy brome. Common St. Johnswort was not influenced by any treatment. Native grass density increased with application of low (454 g/m2) amounts of litter where the grasses were subordinate to common St. Johnswort, and adding native plant litter to the weedy site nearly doubled native grass biomass. Low amounts of finely fragmented litter and high amounts of coarse litter induced native forbs to produce about twice the biomass as found in the non–litter-amended controls. Our study suggests that plant litter may be a component of vegetation that can be managed to shift the plant community toward those plants that are desired.
Variable Impacts of Imazapic Rate on Downy Brome (Bromus tectorum) and Seeded Species in Two Rangeland Communities
Authors: Morris Christo , Monaco Thomas A. , Rigby Craig W. 
Published: June 2009

AbstractThe herbicide imazapic is registered for use on rangelands and provides effective short-term control of certain invasive annual grasses. However, details about optimal application rates for downy brome and susceptibility of simultaneously seeded species are lacking. Thus, we investigated downy brome and seeded species responses to variable rates of imazapic (0, 35, 70, 105, and 140 g ai/ha) in two plant communities (salt desert shrub and Wyoming big sagebrush). In autumn 2003, plots were treated with imazapic and seeded with one of five perennial plant materials (Siberian wheatgrass [‘Vavilov’ and the experimental source Kazak]; prostrate kochia [‘Immigrant’ and the experimental source 6X], and Russian wildrye [‘Bozoisky II’]). Downy brome cover and seeded species establishment were evaluated in spring 2004 and 2006. Downy brome cover in 2004 decreased with increasing imazapic rate at both sites, although more so at the Wyoming big sagebrush site. In 2006, no difference in downy brome cover existed among herbicide rates at the Wyoming big sagebrush site. At the salt desert shrub site, the high rate of imazapic reduced downy brome cover by about 25% compared to untreated plots. ‘Vavilov’ Siberian wheatgrass was the only seeded species with lower downy brome cover in 2006 than 2004. Seeded species establishment increased with imazapic rate in the salt desert shrub community, but in the Wyoming big sagebrush community it peaked at intermediate rates and declined at higher rates. Variation in downy brome control and seeded species establishment might have been associated with differences in precipitation, soil organic matter, and disturbance history between sites. Overall, imazapic was useful for helping establish desirable perennial species, but unless downy brome is reduced below a critical threshold, favorable precipitation can return sites to pretreatment levels within two years.
Approaches for Assessing the Status of Nonnative Plants: A Comparative Analysis
Authors: Fox Alison M. , Gordon Doria R. 
Published: June 2009

AbstractThe magnitude of the invasive plant species problem necessitates prioritization of species for control, regulatory, and public-education programs. Many such priority lists exist but few have been developed according to specified procedures and criteria. We reviewed approaches to assessing the status of nonnative plant species currently occurring in natural areas (status assessments). We identify four generalized types of status assessments, which reflect a gradation from those that simply adopt existing lists from elsewhere (type 1), to those with relatively easy and rapid development and implementation (type 2), to those that are more time-consuming and costly but may be more robust in the face of challenges (types 3 and 4). These latter assessments explicitly have greater transparency, objectivity, and consistency than the other types. We use a matrix of assessment characteristics to distinguish the types of 17 example status assessments. We also review the factors related to assessment intent, scope, structure, content, and implementation that must be considered during the development of new status assessments so that the resulting tool and its products are appropriate for the user's purposes. These analyses should facilitate evaluation of different assessment methods and provide a basis for development of improved assessments. Identification of the relatively low percentage of nonnative plant species that are inflicting ecological and economic harm using well-understood and accepted assessment methods should facilitate a more comprehensive, collective approach to implementation of effective management efforts.
Impacts of Buffelgrass (Pennisetum ciliare) on a Forb Community in South Texas
Authors: Sands Joseph P. , Brennan Leonard A. , Hernández Fidel , Kuvlesky William P. , Gallagher James F. , Ruthven Donald C. , Pittman James E. 
Published: June 2009

AbstractSince the 1950s, many south Texas rangelands have been seeded with buffelgrass, a perennial C4bunchgrass native to Africa that is believed to contribute to reductions in biodiversity. Forb species represent a critical habitat component throughout the breeding period for many wildlife species as seed (summer to fall), as green vegetative material (spring to summer), and as habitat for arthropods (spring to summer). Reductions in richness and diversity of crucial ecosystem components such as forbs and arthropods have large implications for grassland birds and other wildlife. We sampled annual and perennial forbs within 1-m2quadrats on 15 study plots (1 ha;n= 20 quadrats/plot) at Chaparral Wildlife Management Area, in LaSalle and Dimmit counties, Texas, during 2005 and 2006. Study plots were divided into five light-buffelgrass plots (0 to 5% buffelgrass canopy coverage), five moderate-buffelgrass plots (5 to 25% buffelgrass canopy coverage), and five heavy-buffelgrass plots (> 25% buffelgrass canopy coverage). Buffelgrass in study plots was composed of naturalized plants, and was not deliberately planted. During 2005 we observed that plots with > 25% buffelgrass had a 73% reduction in forb canopy of native species, a 64% reduction in native forb species richness, and a 77% reduction in native forb stem density compared to plots with 0 to 5% buffelgrass. These trends in native forb reduction (−79% native forb canopy, −65% forb species richness, −80% forb stem density) were nearly identical in 2006, even with greatly reduced rainfall. Simple linear regression revealed negative relationships between buffelgrass cover, total exotic grass cover (buffelgrass and Lehmann lovegrass), and total grass cover and the richness, coverage, and density of forbs/m2. Reductions in diversity may have larger implications regarding ecosystem function and available useable space and densities of desired bird species such as northern bobwhite.
Effect of Biological Control on Leafy Spurge (Euphorbia esula) and Diversity of Associated Grasslands Over 14 Years
Authors: Lesica Peter , Hanna Dave 
Published: June 2009

AbstractUsing biological control agents to restore native habitats degraded by exotic plants should decrease the abundance of the invaders but should also result in a return toward preinvasion levels of native diversity. However, there are few long-term studies documenting changes in native biological diversity with the decline of an invader. We introduced a biocontrol flea beetle into three Montana grassland sites dominated by leafy spurge and monitored changes in leafy spurge abundance and frequency of associated vascular plants in 48 permanent microplots, in a 530 or 1,960 m2 macroplot immediately before and 14 yr after the release. Density and mass of leafy spurge declined 60 and 69%, respectively, over the 14 yr of the study across the three sites. Total species richness increased by 1.2 species/microplot (21%) between 1994 and 2008 across all three sites, but the increase differed among sites. Mean richness of exotic species was virtually unchanged across the three sites over the course of the study. Graminoid species richness was virtually unchanged across the three sites over the course of the study; most of the increase in diversity was due to the increase in forb richness at all three sites. Release of the biocontrol insects and a subsequent large reduction of leafy spurge were associated with an increase in native diversity after 14 yr, although causality cannot be confidently inferred from these associations because there were no controls. The increase in native diversity was small relative to the decline in leafy spurge abundance, suggesting that significant increases of native alpha diversity in semiarid grasslands may require many decades. Our results also suggest that the response to a decline of an invading species may depend on site quality and history.
Lantana (Lantana camara) Seed Bank Dynamics: Seedling Emergence and Seed Survival
Authors: Vivian-Smith Gabrielle , Panetta F. Dane 
Published: June 2009

AbstractSeed persistence is poorly quantified for invasive plants of subtropical and tropical environments and Lantana camara, one of the world's worst weeds, is no exception. We investigated germination, seedling emergence, and seed survival of two lantana biotypes (Pink and pink-edged red [PER]) in southeastern Queensland, Australia. Controlled experiments were undertaken in 2002 and repeated in 2004, with treatments comprising two differing environmental regimes (irrigated and natural rainfall) and sowing depths (0 and 2 cm). Seed survival and seedling emergence were significantly affected by all factors (time, biotype, environment, sowing depth, and cohort) (P < 0.001). Seed dormancy varied with treatment (environment, sowing depth, biotype, and cohort) (P < 0.001), but declined rapidly after 6 mo. Significant differential responses by the two biotypes to sowing depth and environment were detected for both seed survival and seedling emergence (P < 0.001). Seed mass was consistently lower in the PER biotype at the population level (P < 0.001), but this variation did not adequately explain the differential responses. Moreover, under natural rainfall the magnitude of the biotype effect was unlikely to result in ecologically significant differences. Seed survival after 36 mo under natural rainfall ranged from 6.8 to 21.3%. Best fit regression analysis of the decline in seed survival over time yielded a five-parameter exponential decay model with a lower asymptote approaching −0.38 (% seed survival = [(55 − (−0.38)) · e (k · t)] + −0.38; R2 = 88.5%; 9 df). Environmental conditions and burial affected the slope parameter or k value significantly (P < 0.01). Seed survival projections from the model were greatest for buried seeds under natural rainfall (11 yr) and least under irrigation (3 yr). Experimental data and model projections suggest that lantana has a persistent seed bank and this should be considered in management programs, particularly those aimed at eradication.
Effects of lipid-lowering pharmaceuticals bezafibrate and clofibric acid on lipid metabolism in fathead minnow (Pimephales promelas)
Authors: Weston Anna , Caminada Daniel , Galicia Hector , Fent Karl 
Published: June 2009

Abstract
The lipid-lowering agents bezafibrate and clofibric acid, which occur at concentrations up to 3.1 and 1.6 μL, respectively, are among the most frequently found human pharmaceuticals in the aquatic environment. In contrast to knowledge about their environmental occurrence, little is known about their effects in the environment. The aim of the present study was to analyze effects of these lipid-lowering agents in fish by focusing on their modes of action, lipid metabolism. Fathead minnows were exposed in aquaria to measured concentrations of 0.1, 1.27, 10.18, 101.56, and 106.7 mg/L bezafibrate and to 1.07, 10.75, and 108.91 mg/L clofibric acid for 14 and 21 d, respectively. After exposure, fish liver was analyzed for expression of peroxisome proliferator-activated receptor α (PPARα) by quantitative polymerase chain reaction (PCR), and the PPAR-regulated enzyme fatty acyl-coenzyme-A oxidase (FAO) involved in fatty acid oxidation. Bezafibrate had no effect, either on PPARα expression or on FAO activity, at all concentrations. In contrast, clofibric acid induced FAO activity in male fathead minnows at 108.91 mg/L. No increase in expression of PPARα messenger ribonucleic acid was observed. Egg production was apparently decreased after 21 d of exposure to 108.91 mg/L clofibric acid. The present study demonstrates that bezafibrate has very little or no effect on PPARα expression and FAO activity, but clofibric acid affects FAO activity.