bluuebunny/crossref_metadata_2025 huggingface dataset:
Cultural Management and Nitrogen Source Effects on Ultradwarf Bermudagrass Cultivars
Authors: Hollingsworth B. S. , Guertal E. A. , Walker R. H.
Published: July 2010

Increasingly, vegetative selections from ‘Tifdwarf’, ‘Tifgreen’, or other hybrid bermudagrass [Cynodon dactylon (L). Pers. × C. transvaalensis Burtt Davy] are slowly replacing Tifdwarf as the bermudagrass of choice for putting greens. The cultivars Champion, MS Supreme, TifEagle, and Floradwarf are examples of released ultradwarf bermudagrasses. The objective of this research was to evaluate these four cultivars, Tifdwarf, and an experimental ecotype (Mobile 9) for turf and overseed quality, color, shoot density, and thatch as affected by cultural management and N source. Management programs were: (i) standard, with two vertical mowings at 2.5 cm deep per year plus topdressing, one core aerification, and monthly summer spiking, or (ii) high, with monthly summer vertical mowing at 1.3 cm deep plus topdressing, monthly summer core aerification, and an additional light topdressing each month. Nitrogen sources were urea or methylene urea, each applied at 4 g N m−2 per month. The high management program was too intensive to maintain turf of acceptable quality, because turf could not recover between frequent vertical mowings. Turf color and quality were often improved by application of soluble N, while thatch depth was unaffected by N source. Thatch depth and shoot density were affected by cultivar, with Tifdwarf and MS Supreme having lower thatch depths throughout much of the study. Quality and density of Poa trivialis L. overseeding were largely unaffected by cultivar or management, indicating that a quality overseed could be established through dense bermudagrass turf without intensive cultivation and that overseeding was not affected by the higher shoot densities of the ultradwarf bermudagrasses.
Cool‐Season Grass Development Response to Accumulated Temperature under a Range of Temperature Regimes
Authors: Bartholomew P. W. , Williams R. D.
Published: July 2010

Persistence and productivity of pastures containing mixtures of warm and cool‐season forages may be compromised by interspecific competition when growing periods overlap. An ability to predict the onset and termination of growth of component species would facilitate timing of management interventions to minimize harmful competition in mixed pastures. Experiments were undertaken in controlled environment to assess the use of accumulated temperature values to indicate development stages in three cool‐season grass species, and to evaluate the consistency of this relation under a range of temperature regimes that included variable exposure to below‐freezing temperatures. When grown under light and dark temperature regimes of 22.5 and 7.5, 17.5 and 12.5, 15.0 and 0.0, or 10.0 and 5.0°C, respectively, leaf appearance in Italian ryegrass (Lolium multiflorum Lam.), tall fescue (Festuca arundinacea Schreb), and tall wheatgrass [Elytrigia elongata (Host) Nevski] showed a close linear relationship with accumulated temperature, within each temperature regime. The interval between appearance of successive leaves on seedling mainstem (phyllochron) was increased by increased average daily temperature. In seedlings grown under a 15.0 and 0.0°C temperature regime, phyllochron was increased linearly by up to four 15‐h exposures to −5.0 or −7.5°C dark‐cycle temperatures in successive 24‐h periods. The effects of variation in mean daily temperature and of plant exposure to below‐freezing temperature on phyllochron should be considered if accumulated temperature is used to predict development stage of cool‐season grasses in the field.
Phosphorus and Potassium Leaching under Contrasting Residential Landscape Models Established on a Sandy Soil
Authors: Erickson J. E. , Cisar J. L. , Snyder G. H. , Volin J. C.
Published: July 2010

The quantity of fertilizer applied to residential land use is increasing rapidly with urban expansion. Phosphorus (P) and potassium (K) are essential plant nutrients often included in fertilizers used on residential landscapes. As a result, the potential exists for substantial P and K losses to ground and surface waters via runoff and leaching. Landscape vegetation and maintenance protocols play important roles in mitigating nutrient losses. Therefore, the objectives of this comparative study were to examine fertilizer P and K leaching losses from contrasting residential landscape models established on a sandy soil. Four replications each of a St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] monoculture (SA) and a mixed‐species (MS) landscape were randomly assigned to 47.5‐m2 plots. The use of common management practices was part of each landscape model, as granular fertilizers were applied to the SA monoculture routinely (bimonthly) throughout the study (61 kg P ha−1 and 424 kg K ha−1) but only during establishment for the MS landscape (105 kg P ha−1 and 630 kg K ha−1). Losses of P and K in surface runoff were negligible. However, during the 45 mo of data collection, cumulative mean P leached was 37.8 kg ha−1 on the MS model and 22.9 kg ha−1 on the SA model, while cumulative mean K leached was 346 kg ha−1 on the MS landscape and 185 kg ha−1 on the SA landscape. Notably, leaching losses were high during establishment and following intense precipitation, but the SA landscape model minimized these losses compared with the MS model. Regardless of landscape, leaching losses of P, and perhaps K, were high enough to raise concern over ecological impacts on neighboring hydrologically linked systems.
Analysis of Stalk Rot Resistance and Genetic Diversity among Drought Tolerant Sorghum Genotypes
Authors: Tesso Tesfaye T. , Claflin Larry E. , Tuinstra Mitchell R.
Published: July 2010

Forty‐five drought tolerant sorghum [Sorghum bicolor (L.) Moench] genotypes were screened for stalk rot resistance by artificial inoculation with Fusarium proliferatum in field trials near Manhattan, KS, in 2000. Four lines, SC134, SC1154, SC1039, and SC564, were identified with lesions that were smaller than the standard resistant check, SC599. These lines and four other checks were intercrossed in a Design II mating scheme with ‘AWheatland’ and ‘ARedlan’ to produce hybrids for further testing. The inbred parent lines and corresponding hybrids were evaluated for resistance to four major stalk rot pathogens, F. proliferatum, F. thapsinum, F. andiyazi, and Macrophomina phaseolina, using randomized complete block designs in field trials near Manhattan and Hesston, KS, in 2001. Significant differences in lesion length were detected among the inbred parent lines and their corresponding hybrids. Comparisons among entries indicated that crosses of SC701 and SC564 were susceptible and produced very large lesions following inoculation with each of the stalk rot pathogens evaluated in this study. Only small lesions were produced in SC599 and its hybrids following inoculation with either Fusarium species or M. phaseolina SC134 also exhibited high levels of resistance to Fusarium species and SC35 to M. phaseolina Comparisons among pathogens showed that inoculations with M. phaseolina produced larger lesions than the Fusarium species in most sorghum genotypes. The most resistant accessions in these studies were all from East Africa; therefore, an analysis of genetic diversity was conducted to evaluate the pattern of genetic relationships among the full set of drought tolerant lines. DNA fingerprinting followed by cluster analyses grouped the entries into five distinct clusters, mainly according to geographical origin. Three of the resistant lines grouped together in a cluster that contained mostly Ethiopian landraces while SC599 grouped in another cluster.
Quantitative Trait Loci Associated with Seed Dormancy in Rice
Authors: Wan J. M. , Cao Y. J. , Wang C. M. , Ikehashi H.
Published: July 2010

Seed dormancy is a key agronomic trait related to the quality of seed and rice production because it imparts resistance to preharvest sprouting. A population was constructed from a three‐way cross, IR50/Tatsumimochi//Miyukimochi, in which IR50 was an indica donor of strong seed dormancy and Tatsumimochi and Miyukimochi were nondormant japonica cultivars. Seed dormancy was tested for 166 F1 plants of the three‐way cross and their progeny population (F2). A total of 108 simple sequence repeats (SSR) markers were mapped on 12 rice chromosomes, and quantitative trait locus (QTL) analysis was performed for seed dormancy in the two segregating generations. Three putative QTLs affecting seed dormancy were detected on chromosomes 1, 3, and 7 in the F1 generation. Phenotypic variations explained by each QTL ranged from 4 to 21%, indicating that seed dormancy is affected by a number of minor genetic effects. The putative QTLs on chromosomes 1 and 3 were also detected in the F2 generation at the same map sites. Considering the present and past results there are a number of genetic factors that affect rice seed dormancy; however, the two SSR markers on chromosomes 1 and 3 could be used to develop near‐isogenic lines (NILs) for map‐based cloning of seed dormancy genes in the regions to thus improve the dormancy of japonica rice.
Introgression of Perennial Teosinte Genome into Maize and Identification of Genomic In Situ Hybridization and Microsatellite Markers
Authors: Tang Qilin , Rong Tingzhao , Song Yunchun , Yang Junpin , Pan Guangtang , Li Wanchen , Huang Yubi , Cao Moju
Published: July 2010

To transfer desirable characters from perennial teosinte [Zea perennis (Hitchc.) Reeves & Mangelsd.] into maize (Z. mays L.), we have generated an interspecific hybrid and its backcross generations (BC1F3). The maize × perennial teosinte BC1F3 (MZI202) resembled maize, with chromosome number 2n = 20. MZI202 was studied by multicolor genomic in situ hybridization (McGISH) and simple‐sequence repeat (SSR) microsatellites markers. The McGISH experiments provided direct evidence that MZI202 was a maize–perennial teosinte substitution line with introgression of three alien chromosomes from perennial teosinte. The SSR assay further confirmed that a single chromosome 6 and the pair of chromosome 10 of maize were replaced by perennial teosinte chromosomes in MZI202.
Molecular Characterization of Slow Leaf‐Rusting Resistance in Wheat
Authors: Xu Xiangyang , Bai Guihua , Carver Brett F. , Shaner Gregory E. , Hunger Robert M.
Published: July 2010

Slow leaf‐rusting resistance in wheat (Triticum aestivum L) is gaining acceptance as a breeding objective because of its durability in comparison with race‐specific resistance. CI 13227 was previously reported to provide the highest level of slow leaf‐rusting resistance. The objective of this study was to characterize the slow leaf‐rusting resistance conferred by CI 13227 using molecular markers. A population of recombinant inbred lines (RILs) derived from CI 13227/Suwon 92 was evaluated for final severity (FS), area under disease progress curve (AUDPC), infection rate (IR), and infection duration (ID) of leaf rust. Four hundred fifty‐nine amplified fragment length polymorphism (AFLP) markers and 28 simple sequence repeat (SSR) markers were analyzed in the population. Two quantitative trait loci (QTL), designated as QLr.osu‐2B and QLr.osu‐7BL, were consistently associated with AUDPC, FS, and IR of leaf rust, caused by Puccinia triticina (previously P. recondita Rob. Ex Desm. f. sp. tritici). The percentages of phenotypic variance explained by each QTL varied with experiments and traits, ranging from 13.4 to 18.8% for AUDPC, 12.5 to 20.8% for FS, and 12.9 to 16.1% for IR. The third QTL for leaf rust ID, designated as QLrid.osu‐2DS, was located on chromosome 2DS and explained 26.4 and 21.47% of the phenotypic variance in 1994 and 1995, respectively. Both the QTL and correlation analysis indicate reasonable progress in leaf‐rusting resistance by selecting for final severity. SSR markers closely associated with QLr.osu‐2B or QLr.osu‐7BL have potential to be used in marker‐assisted selection (MAS) for durable leaf rust resistant cultivars.
Seedling Drought Tolerance in Upland Cotton
Authors: Basal H. , Smith C. W. , Thaxton P. S. , Hemphill J. K.
Published: July 2010

Combining root morphological and plant physiological traits associated with drought tolerance should result in improved drought resistance in cotton (Gossypium hirsutum L.). This study was designed to evaluate the response of root growth of selected Converted Race Stocks (CRS), TAM94L‐25, and ‘Lankart 142’ (LK 142) under water stress and nonstressed conditions, and to compare their excised leaf water loss (ELWL). Two putative seedling drought tolerant and two putative nonseedling drought tolerant CRS lines, plus TAM94L‐25 and LK 142, were grown with and without moisture stress in a greenhouse at College Station, TX, in 2002 and 2003. The robust rooting CRS, M‐9044‐0031‐R and M‐8744‐0175‐R, had longer tap root length (RL), higher lateral root number (LRN), greater total root dry weight (TRDW), greater root weight per unit length of tap root (W/L), and greater shoot dry weight (SDW) than the nonrobust CRS M‐9044‐0045‐NR and M‐9044‐0057‐NR, and LK 142 regardless of water regime. Two cycles of seedling drought resulted in an increase in LRN in M‐9044‐0057‐NR, TAM94L‐25, and LK 142. SDW and TRDW were highly correlated and SDW was associated with W/L. The excised leaf water loss (ELWL) tended to be greater in the NR CRS lines when measured at 30‐m intervals for 8 h. Results suggested (i) that root parameters, initial water content (IWC), and ELWL, could be used as a reliable selection criteria for drought tolerance and (ii) that day‐neutral CRS accessions could be used as a source of useful genetic variability for a cotton drought tolerance improvement program.
Physical Mapping of Wheat and Rye Expressed Sequence Tag–Simple Sequence Repeats on Wheat Chromosomes
Authors: Mohan Amita , Goyal Aakash , Singh Ravinder , Balyan Harindra S. , Gupta Pushpendra K.
Published: July 2010

Six hundred and seventy two loci belonging to 275 expressed sequence tag–simple sequence repeats [EST–SSRs, including 93 wheat (Triticum aestivum L.) and 182 rye (Secale cereale L.) EST–SSRs] were physically mapped on 21 wheat chromosomes. The mapping involved two approaches, the wet‐lab approach involving use of deletion stocks and the in silico approach involving matching with ESTs that were previously mapped. The number of loci per EST–SSR mapped using the in silico approach was almost double the number of loci mapped using the wet‐lab approach (using deletion stocks). The distribution of loci on the three subgenomes, on the seven homoeologous groups and on the 21 individual chromosomes was nonrandom (P ≪ 0.01). Long arms had disproportionately (relative to the difference in DNA content) higher number of loci, with more loci mapped to the distal regions of chromosome arms. A fairly high proportion of EST–SSRs had multiple loci, which were largely (81%) homoeoloci. Rye EST–SSRs showed a high level of transferability (≈77%) to the wheat genome. Putative functions were assigned to 216 SSR‐containing ESTs through homology searches against the protein database. As many as 104 SSR‐containing ESTs (a subset of the above ESTs) were also mapped to the 12 rice chromosomes, which corresponded with the known homology between wheat and rice chromosomes. These physical maps of EST–SSRs should prove useful for comparative genomics, gene tagging, fine mapping, and cloning of genes and QTLs.
Quantitative Determination of Phytate and Inorganic Phosphorus for Maize Breeding
Authors: Lorenz Aaron J. , Scott M. Paul , Lamkey Kendall R.
Published: July 2010

Phytate is the dominant storage form of phosphorus (P) in mature cereal and oil grains. Phosphorus bound in phytate is nutritionally unavailable to monogastric animals and thus contributes to water pollution because it is excreted in the waste. Also, phytate can chelate certain minerals and exacerbate human mineral deficiencies. Our primary objective was to develop a rapid and inexpensive method of measuring phytate and inorganic P (Pi) concentrations in maize (Zea mays L.). The procedure reported herein was derived from previously published assays and used to screen 50 inbred lines to determine its potential in a selection program. Grain yield, protein, oil, methionine, lysine, tryptophan, and kernel weight were also measured. Field repeatability values for phytate and Pi (0.78 and 0.91, respectively) suggest that our protocol can be used to make heritable measurements on both traits. Phytate measurements taken with the procedure reported herein matched closely those obtained through ion exchange. The combination of adequate precision and simplicity make this method ideal for breeders interested in improving Pi and phytate levels simultaneously. The positive phytate:protein correlation reported commonly was also detected in this study. A relationship between phytate and kernel weight indicates that selection for low phytate may result in larger kernels.
The FAD2 Gene Family of Soybean: Insights into the Structural and Functional Divergence of a Paleopolyploid Genome
Authors: Schlueter Jessica A. , Vasylenko‐Sanders Iryna F. , Deshpande Shweta , Yi Jing , Siegfried Majesta , Roe Bruce A. , Schlueter Shannon D. , Scheffler Brian E. , Shoemaker Randy C.
Published: July 2010

The ω‐6 fatty acid desaturase (FAD2) gene family in soybean [Glycine max (L.) Merr.] consists of at least five members in four regions of the genome and are responsible for the conversion of oleic acid to linoleic acid. Here we report the identification of two new ω‐6 fatty acid desaturase (FAD2) gene copies from soybean expressed sequence tags (ESTs). Four bacterial artificial chromosomes (BACs) containing five FAD2 genes were sequenced to investigate structural and functional conservation between duplicate loci. Sequence comparisons show that the soybean genome is a mosaic, with some duplicate regions retaining high sequence conservation in both genic and intergenic regions, while others have only the FAD2 genes in common. Genetic mapping using SSRs from within the BAC sequences showed that two BACs with high sequence homeology mapped to linkage groups I and O; these groups share syntenic markers. Another BAC mapped to linkage group L. The fourth BAC could not be mapped. Reverse transcriptase–polymerase chain reaction (RT–PCR) analysis of the five FAD2 genes showed that the FAD2‐2B and FAD2‐2C copies were the best candidates for temperature‐dependent expression changes in developing pod tissue. Semiquantitative RT‐PCR confirmed these results, with FAD2‐2C showing upward of an eightfold increase in expression in developing pods grown in cooler conditions relative to those grown in warm conditions. The implications of these results suggest a candidate gene for controlling the levels of linoleic acid in developing pods grown in cooler climates.
Combining Abilities and Heterosis for Forage Yield among High‐Yielding Accessions of the Alfalfa Core Collection
Authors: Bhandari H. S. , Pierce C. A. , Murray L. W. , Ray I. M.
Published: July 2010

Characterization of genetic parameters in plant germplasm repository populations can facilitate their utilization in commercial breeding programs. This study investigated genetic combining abilities and heterosis for forage yield among diallel hybrids derived from nine previously selected high‐yielding accessions of the USDA‐ARS National Plant Germplasm System core collection of alfalfa (Medicago sativa subsp. sativa L.). These accessions originated from Turkey, South Africa, Greece, Afghanistan, Israel, Uzbekistan, Mexico, Morocco, and the USA. Forage yield response of the parents and their hybrids was determined near Las Cruces, New Mexico. General combining ability (GCA) and specific combining ability (SCA) effects were significant. The magnitudes of the GCA effects were about 5% (<0.71 Mg ha−1) relative to the mean yield of the parents (15.4 Mg ha−1). The Turkey, Afghanistan, and Uzbekistan accessions demonstrated significant positive GCA effects. Accessions from Greece and Morocco demonstrated negative GCA effects. Six hybrids outperformed the average of six commercial cultivars. Five of these six hybrids demonstrated positive SCA effects. Midparent heterosis ranged from –17 to 17%. The results indicate that crossing between alfalfa populations possessing high per se performance and different fall regrowth responses is likely to produce a higher proportion of high‐yielding hybrids in environments experiencing intermittent subfreezing winter conditions.
Reduction of a Triticum monococcum Chromosome Segment Carrying the Softness Genes Pina and Pinb Translocated to Bread Wheat
Authors: Bonafede Marcos , Kong Lingrang , Tranquilli Gabriela , Ohm Herbert , Dubcovsky Jorge
Published: July 2010

Endosperm texture, i.e., the hardness or softness of the grain, is an important trait because it determines many end‐use properties of wheat (Triticum aestivum L.). It is primarily controlled by the puroindoline genes (Pina and Pinb) at the Hardness (Ha) locus, mapped on the short arm of chromosome 5D. The introgression of functional Pin genes from diploid wheat Triticum monococcum L. chromosome 5Am into hexaploid wheat resulted in softer grains, suggesting that this translocation might be useful for soft wheat breeders. However, the translocated segment includes a large portion of the 5Am short arm and may carry detrimental genes for agronomic performance. In this study we have generated a backcross (BC) population of 210 individuals where 5A‐5Am homeologous recombination was induced by the ph1b mutation to recover individuals with a reduced translocated segment. A map of this region was constructed using specific sequence tagged site (STS) markers for the three T. monococcum Ha–related genes, the completely linked BGGP gene, three wheat ESTs (BG606847, BF474606, and BQ168958), and two microsatellite markers. Eight plants with recombination events between XBggp and the closest proximal locus BG606847 were identified. Of these, four have the desired T. monococcum allele at the Ha locus. These plants carry a 6.3‐cM segment of T. monococcum chromatin proximal to the Ha locus. This germplasm, which will be publicly available, and the molecular markers developed in this study will be valuable tools for soft wheat breeding programs.
Polyploidy and Crop Improvement
Authors: Udall Joshua A. , Wendel Jonathan F.
Published: July 2010

All crop plants are polyploid and some genomes have been duplicated more recently than others. Advancements in cytogenetic and molecular tools, including high‐density genetic mapping, florescent in situ hybridization, and genome and EST sequencing, have enabled new insights into genome composition and the history of genome duplications in crop plants. We review this evidence and discuss the relevance of genome duplication to crop improvement. Polyploidy provides genome buffering, increased allelic diversity and heterozygosity, and permits novel phenotypic variation to be generated. Polyploid formation is often accompanied with loss of duplicated chromatin, changes in gene expression, novel epistatic interactions, and endosperm effects. All of these factors need be considered in a genome‐wide context for optimizing marker assisted selection and crop plant improvement.
A Large‐Effect QTL for Grain Yield under Reproductive‐Stage Drought Stress in Upland Rice
Authors: Bernier Jérôme , Kumar Arvind , Ramaiah Venuprasad , Spaner Dean , Atlin Gary
Published: July 2010

Genetic control of yield under reproductive‐stage drought stress was studied in a population of 436 random F3–derived lines from a cross between the upland rice (Oryza sativa L.) cultivars Vandana and Way Rarem. Screening was conducted under upland conditions at IRRI during the dry seasons of 2005 and 2006. Lines were evaluated in drought stress and nonstress trials in both years to identify QTL contributing to drought resistance. For QTL detection, a set of random lines and the highest and lowest‐yielding lines under both stress and nonstress conditions were genotyped by 126 SSR markers. A QTL (qtl12.1) with a large effect on grain yield under stress was detected on Chromosome 12 in both years. The whole population was genotyped for additional markers on Chromosome 12, allowing QTL localization to a 10.2 cM region between SSR markers RM28048 and RM511. Under stress conditions, the locus also increased harvest index, biomass yield, and plant height while reducing the number of days to flowering. Under nonstress conditions, qtl12.1 did not significantly affect any trait. The additive effect of this QTL on grain yield under stress was 172 kg ha−1 per year over the 2 yr of testing, representing 47% of the average yield under stress and explaining 51% of the genetic variance. The yield‐increasing allele was derived from the susceptible parent, Way Rarem, suggesting an epistatic effect. This is the first QTL reported in rice having a large and repeatable effect on grain yield under severe drought stress in the field.
Causal Inference and Scientific Paradigms in Epidemiology
Authors: S. Coughlin Steven
Published: July 2010

This anthology of articles on causal inference and scientific paradigms in epidemiology covers several important topics including the search for causal explanations, the strengths and limitations of causal criteria, quantitative approaches for assessing causal relationships that are relevant to epidemiology and emerging paradigms in epidemiologic research. In order to provide historical context, an overview of philosophical and historical developments relevant to causal inference in epidemiology and public health is also provided. Several theoretical and applied aspects of causal inference are dealt with. The aim of this Ebook is not only to summarize important developments in causal inference in epidemiology but also to identify possible ways to enhance the search for causal explanations for diseases and injuries. Examples are provided from such fields as chronic disease epidemiology, Veterans health, and environmental epidemiology. A particular goal of the Ebook is to provide ideas for strengthening causal inference in epidemiology in the context of refined research paradigms. These topics are important because the results of epidemiologic studies contribute to generalizable knowledge by clarifying the causes of diseases, by combining epidemiologic data with information from other disciplines (for example, psychology and industrial hygiene), by evaluating the consistency of epidemiologic data with etiological hypotheses about causation, and by providing the basis for evaluating procedures for health promotion and prevention and public health practices.
Research Paradigms and the Strengthening of Causal Inference in Epidemiology
Authors: Steven S.Coughlin
Published: July 2010

Changes in research paradigms and theories about disease causation have frequently led to refinements in frameworks for causal inference. Among the most promising paradigm shifts in contemporary epidemiology has been an increasing willingness to examine disease etiology using a multilevel or systems approach and a parallel trend towards the mathematization of causal inference. However, these two important developments (adoption of a multilevel or systems approach for epidemiologic research and use of quantitative models for causal inference) have not been adequately linked. One important impediment to reaching the full potential of multilevel studies is the need for further refinement of quantitative and graphical models for causal inference that are suitable for emerging research paradigms. More efforts should be made to clarify conceptually what approaches work best for identifying causal relationships in the context of complex systems. Optimal approaches to causal inference are not necessarily identical across epidemiology subdisciplines and researchers should not assume that there is one correct or optimal theory of causality that accounts for causal relationships identified in epidemiologic research.
Does polyploidy occur in central European species of the family Sphaeriidae (Mollusca: Bivalvia)?
Authors: Kořínková Tereza , Morávková Alena
Published: July 2010

Some representatives of the bivalve family Sphaeriidae are assumed to be polyploid. In this study, 11 sphaeriid species (nine of the genus Pisidium, one of Musculium, and one of Sphaerium) inhabiting central Europe were studied karyologically, 10 of them for the first time. Analysis revealed high chromosome numbers (from 140 to 240). To elucidate the origin of high chromosome numbers, DNA contents were measured by flow cytometry in 5 of the studied species and, for comparison, in S. corneum and S. nucleus, which are known to be diploid (2n=30). Species with high chromosome counts yielded very similar DNA contents that are not higher than in the related species with low diploid numbers. This finding contradicts a possible origin of these species by recent polyploidization or hybridization of related species. Chromosome complements of the investigated species with high chromosome numbers differ from those with low 2n in their small chromosome size and the high proportion of subtelo- or acrocentric chromosomes. This indicates their possible origin either by an ancient polyplodization event followed by chromosomal rearrangements or by multiple chromosome fissions.
Morphometry of non-native black bullhead Ameiurus melas from Slovakia
Authors: Novomeská Andrea , Kováč Vladimír , Katina Stanislav
Published: July 2010

The study on the external morphology of the non-native black bullhead (Ameiurus melas) was carried out on a population from Slovakia, based on triple regression and geometrical analysis. The breakpoints distribution in distance-based morphometric characters indicated that black bullhead reached its definitive phenotype early in ontogeny. Ontogenetic changes in external morphology occurred continuously throughout the whole size-range of the sample examined, and inter-individual morphological variation was very low. Such uniformity may reflect the possible founder effect and/or little phenotypic plasticity of this non-native population. No sexual dimorphism was observed. This is the first detailed study on external morphology of the species, and as such it contributes to the assessment of phenotypic plasticity and/or overall morphological variability of black bullhead’s invasive populations.
More female red foxes Vulpes vulpes on bait sites in spring
Authors: Galby Jens , Hjeljord Olav
Published: July 2010

The red fox Vulpes vulpes has traditionally been subjected to control efforts throughout much of its range. In this article, we present data on the sex and age composition of red foxes culled at bait sites in an area of southeastern Norway. While an excess of males were shot in early and mid‐winter, equal proportions of males and females were shot in early spring. Apparently, females are more nutritionally stressed in March due to pregnancy and therefore visit bait sites more frequently. Culling earlier in winter will predominantly remove males and will bias the sex composition in the population towards females.
Nest predation in declining populations of common eiders Somateria mollissima: an experimental evaluation of the role of hooded crows Corvus cornix
Authors: Stien Jennifer , Yoccoz Nigel G. , Ims Rolf A.
Published: July 2010

We evaluated the effect of the removal of hooded crows Corvus cornix on common eider Somateria mollissima nesting success using a partial Before and After Comparison of Impact (BACI) design over three years in two eider breeding colonies (Håk⊘ya and Grind⊘ya) in northern Norway. These breeding colonies had over the last decades been subject to severe declines in number of breeding birds and it was suspected that increasing nest predation by crows was contributing to the declines. Eider nesting success was monitored in both colonies during 2006‐2008. Crows were removed by live‐trapping from Håk⊘ya in 2007 and from Grind⊘ya in 2008. We monitored the number of nesting pairs of crows and general crow activity. Crow removal was generally successful in reducing the number of established territorial and visiting crows. Modelling of daily nesting success probabilities according to a logistic exposure model revealed that eider nests found at the start of the season had a much lower probability of success than nests found later on in the season. This is likely to be due in part to the increase in number of active nests during the first half of the season. The effect of crow removal appeared to differ between the two colonies. Eider nesting success on Håk⊘ya increased from 61% in the pre‐removal year 2006 to 80% during crow removal in 2007 and declined to 74% in the post‐removal year 2008. In contrast, nesting success on Grind⊘ya remained constantly low (38‐40%) during the same period. This difference between the two colonies could be explained by a difference in predation pressure, or by a higher general disturbance level on Grind⊘ya making unattended nests vulnerable to predation by a range of alternative predator species acting compensatory to the removal of crows. New investigations should be undertaken to clarify the interaction between crows and other nest predators in determining eider nesting success. Where compensation appears to occur, conditions for this process should be investigated. This will help to indicate when crow removal can be effective and which other actions can be employed to increase common eider nesting success.
The role of ultrasonography and FDG-PET in axillary lymph node staging of breast cancer
Authors: Ahn Jhii-Hyun , Son Eun Ju , Kim Jeong-Ah , Youk Ji Hyun , Kim Eun-Kyung , Kwak Jin Young , Ryu Young Hoon , Jeong Joon
Published: July 2010

Background: The presence of axillary lymph node metastasis is the most important prognostic factor and an essential part of staging and prognosis of breast cancer.

Purpose: To elucidate the usefulness and accuracy of ultrasonography (US), fluorodeoxyglucose positron emission tomography (FDG-PET) scan, and combined analysis for axillary lymph node staging in breast cancer.

Material and Methods: A total of 250 consecutive breast cancer patients who had undergone US, FDG-PET, and sentinel lymph node biopsy (SLNB) before surgery from January 2005 to December 2006 were included in the study. If an axillary lymph node had a length to width ratio ≤1.5 or cortical thickening ≥3 mm or compression of the hilum on US, focal hot uptake (maximal standardized uptake value, SUVmax ≥2.0) in the ipsilateral axilla on FDG-PET, it was considered to be a metastatic lymph node. In combined analysis of US and FDG-PET, the interpretation was considered positive if at least two of any of the criteria were met. Each imaging finding was compared with a pathologic report regarding the presence of axillary lymph node metastasis, the number of metastatic lymph nodes, and the T stage of the breast mass.

Results: Pathologically confirmed axillary lymph node metastasis was noted in 73 cases (29.2%). The mean number of metastatic lymph nodes in pathology was 3.1 ± 3.2, and the size of breast cancer was 2.0 ± 1.04 cm. In the detection of lymph node metastasis, the diagnostic accuracy of US was 78.8% and that of FDG-PET was 76.4%. On combined US and FDG-PET, accuracy was improved (91.6%). The number of metastatic lymph nodes on pathology was correlated with the positivity of US and FDG-PET ( P < 0.01).

Conclusion: Combined evaluation of US and FDG-PET was a sensitive and accurate method for axillary lymph node staging in breast cancer.
Edward Robson's list of the rarer plants of County Durham
Authors: HORSMAN FRANK , DAVIS PETER
Published: July 2010

Davis and Graham (1981) described the botanical activities of the Darlington Quakers, Stephen Robson (1741–1779) and his nephew, Edward Robson (1763–1813), and attributed to the latter a list of rarer Durham plants, Plantae rariores agro Dunelmensi indigenae, which was privately printed in 1798. Further evidence has now been found which confirms that Edward Robson was the compiler of this list, which was circulated widely to contemporary botanists. Some preliminary comments are made on the significance of the list, and Edward's importance as a field botanist of his times is further emphasised.
Complexes in the Photocatalytic Reaction of CO2 and H2O: Theoretical Studies
Authors: Luo Dongmei , Zhang Ning , Hong Sanguo , Wu Huanwen , Liu Zhihua
Published: July 2010

: Complexes (H2O/CO2, e–(H2O/CO2) and h+–(H2O/CO2)) in the reaction system of CO2 photoreduction with H2O were researched by B3LYP and MP2 methods along with natural bond orbital (NBO) analysis. Geometries of these complexes were optimized and frequencies analysis performed. H2O/CO2 captured photo-induced electron and hole produced e–(H2O/CO2) and h+–(H2O/CO2), respectively. The results revealed that CO2 and H2O molecules could be activated by the photo-induced electrons and holes, and each of these complexes possessed two isomers. Due to the effect of photo-induced electrons, the bond length of C=O and H-O were lengthened, while H-O bonds were shortened, influenced by holes. The infrared (IR) adsorption frequencies of these complexes were different from that of CO2 and H2O, which might be attributed to the synergistic effect and which could not be captured experimentally.
Review on the Functional Determinants and Durability of Shape Memory Polymers
Authors: Pretsch Thorsten
Published: July 2010

Shape memory polymers (SMP) belong to the class of stimuli-responsive materials and have generated significant research interest. Their capability to retain an imposed, temporary shape and to recover the initial, permanent shape upon exposure to an external stimulus depends on the “functional determinants”, which in simplistic terms, can be divided into structural/morphological and processing/environmental factors. The primary aim of the first part of this review is to reflect the knowledge about these fundamental relationships. In a next step, recent advances in shape memory polymer composites are summarized. In contrast to earlier reviews, studies on the impairment of shape memory properties through various factors, such as aging, compression and hibernation, lubricants, UV light and thermo-mechanical cycling, are extensively reviewed. Apart from summarizing the state-of-the-art in SMP research, recent progress is commented.
Preparation of aminoethyl glycosides for glycoconjugation
Authors: Šardzík Robert , Noble Gavin T , Weissenborn Martin J , Martin Andrew , Webb Simon J , Flitsch Sabine L
Published: July 2010

The synthesis of a number of aminoethyl glycosides of cell-surface carbohydrates, which are important intermediates for glycoarray synthesis, is described. A set of protocols was developed which provide these intermediates, in a short number of steps, from commercially available starting materials.
Predictability Associated with Exit Examinations: A Literature Review
Authors: Harding Mariann
Published: July 2010

The aims of this review are to study the accuracy of commercial examinations for predicting NCLEX-RN
®
success to determine whether there are significant differences in scores for graduates who pass the NCLEX-RN on their first attempt compared with those who do not and to discuss the implications of the findings in relation to progression policies. The most widely reported relationships between standardized test scores and NCLEX-RN success are associated with the Health Education Systems, Inc. (HESI) Exit Examination. In studies conducted over 4 consecutive years with a total of 17,432 students, HESI was found to be 96.4% to 98.3% accurate in predicting NCLEX-RN success for the highest scoring students. When HESI Exit Examination scores are used in logistic regression models, they are useful only in predicting NCLEX-RN success, not failure. These findings are consistent with reports regarding other computerized examinations. There is mixed evidence that these progression policies result in increased NCLEX-RN pass rates.
Integrating Psychosocial Skills into a Medical-Surgical Curriculum in a Baccalaureate Nursing Program
Authors: Christoffersen Jean , Barron Anne-Marie , Lynch Marla , Caroline Harlene
Published: July 2010

With the increasing acuity levels of hospitalized patients, faculty members struggle with accessing clinical sites for undergraduate students. Teaching students how to interact with patients and their families can often take second place to attending to the many needs and safety issues in caring for acutely ill individuals, particularly in medical-surgical settings. Over the past several years, the psychiatric and medical-surgical faculty members in the nursing department of a college in Boston have struggled with how best to prepare students for both the physical and psychosocial aspects of care. In this article, the evolution of our psychiatric consultation-liaison model is discussed.
Posterior Chamber Lens Implantation With Scleral Fixation in Children With Traumatic Cataract
Authors: Caca Ihsan , Sahin Alparslan , Ari Seyhmus , Alakus Fuat
Published: July 2010

Purpose:

To evaluate the outcomes of posterior chamber lens implantation with scleral fixation (SF-PCIOL) in children with traumatic cataract.

Methods:

Twenty-four eyes of 24 cases were included. All patients had corneal or corneoscleral lacerations that were primarily repaired. Traumatic cataract subsequently developed and SF-PCIOL was performed due to insufficient posterior capsule support.

Results:

The average age of the patients was 5.8 years (range: 4 to 10 years). All cases had SF-PCIOL implanted via internal route using triangular double scleral flaps made of 9-0 polypropylene after a complete anterior vitrectomy. Average follow-up was 14.6 ± 4.3 months (range: 11 to 18 months). Visual acuity was increased at the last visit in 23 (96%) patients. Common postoperative complications were fibrinous reaction in 6 (25%) patients, transient intraocular pressure increase in 4 (17%) patients, membrane formation requiring removal in 1 (4%) patient, transient intraocular hemorrhage as vitreous hemorrhage in 1 (4%) patient, and retinal detachment in 1 (4%) patient after the postoperative second month.

Conclusion:

SF-PCIOL is an effective and reliable method in patients with pediatric traumatic cataract who had insufficient posterior capsule support.
Preferences of Pediatric Ophthalmologists and Vitreoretinal Surgeons of the Treatment of Scleral Perforations During Strabismus Surgery
Authors: Hwang Christopher K. , Phoenix Vidya P. , Hutchinson Amy K.
Published: July 2010

Purpose:

To evaluate the preferences of pediatric ophthalmologists and vitreoretinal surgeons with regard to the initial management of scleral perforation during strabismus surgery and to determine whether they perceived one mode of treatment conferred a significant advantage over another in terms of the complication rate.

Methods:

Six hundred sixty-five pediatric ophthalmologists and 494 vitreoretinal surgeons registered with their respective national organizations were invited by an e-mail to respond to an anonymous, web-based survey. The responses to the survey were compared between groups.

Results:

A total of 169 ophthalmologists participated, 133 of whom were pediatric ophthalmologists and 36 vitreoretinal surgeons. Significantly more pediatric ophthalmologists than vitreoretinal surgeons recommend initially managing scleral perforation by observation (
P
= .001). Among pediatric ophthalmologists, method of treatment was not perceived to affect outcome (
P
= .75). However, laser photocoagulation was perceived to result in the best outcome among vitreoretinal surgeons (
P
= .03).

Conclusion:

Significant differences exist among pediatric ophthalmologist and vitreoretinal surgeon management preferences and perceived treatment outcomes for scleral perforation.
Death in the Nursing Home
Authors: Anderson Keith A. , Ewen Heidi H.
Published: July 2010

The grief that nurses experience when patients and residents die can be complex and has been linked to both problematic (e.g., depression) and beneficial (e.g., gains in coping) outcomes. In this study, 380 nursing assistants working in the nursing home setting were surveyed to gain an understanding of the relationship between grief and well-being. Findings indicated that participants experienced both distress and growth in their grief. Those who experienced greater distress from grief reported significantly higher levels of burnout and lower levels of psychological and physical well-being. Conversely, participants who experienced greater growth from their grief reported significantly lower levels of burnout, higher levels of psychological and physical well-being, and higher levels of job satisfaction. These findings suggest that grief may be an important determinant of well-being in nursing assistants, which, in turn, may impact quality of care in the nursing home.
Storytelling by Community-Dwelling Older Adults
Authors: Mastel-Smith Beth , Binder Brenda , Hersch Gayle , Davidson Harriett A. , Walsh Teresa
Published: July 2010

The purpose of this exploratory, qualitative study was to investigate storytelling by home care clients to their home care workers (HCWs). Specific research questions were: (a) When does storytelling by a care recipient occur during usual care?; (b) How do HCWs engage older clients in storytelling?; (c) How do HCWs respond to the stories told by clients?; and (d) What is the perceived effect of storytelling by older clients on the relationship between the client and the HCW? Two focus groups consisting of 10 HCWs each were conducted. Verbatim transcripts of both focus groups were analyzed using the constant comparative analysis method. Categories and concepts were identified. Characteristics of the HCW and client set the stage for storytelling. The process of storytelling included context, triggers, and temporal aspects. HCWs also shared the content of stories, the impact on their relationship with the client, and the perceived effect on each individual. A visual model depicting the nature of storytelling in association with the care of older clients is presented.
Valuations for Matroid Polytope Subdivisions
Authors: Ardila Federico , Fink Alex , Rincón Felipe
Published: July 2010

We prove that the ranks of the subsets and the activities of the bases of a
matroid define valuations for the subdivisions of a matroid polytope into
smaller matroid polytopes.
Why TEI stand-off annotation doesn't quite work
Authors: Bański Piotr
Published: July 2010

The present submission focuses on the concept of stand-off annotation as it is implemented in the current version of the TEI Guidelines. We look at the motivation for choosing the stand-off approach to encoding Language Resources, briefly recount the history of the concept within the broadly conceived TEI setting (since TEI P3 and the LT NSL suite, through CES and XCES, ending in TEI P5), review the various kinds of hyperlink semantics and identify three kinds of reasons for the poor uptake of the TEI-recommended stand-off annotation approach to corpus encoding. We also suggest some solutions that may contribute to a change in the current state of affairs.