bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimation of Preferential Pairing Rates in Second-Generation Autotetraploid Pacific Oysters (Crassostrea gigas)
Authors: Curole Jason P , Hedgecock Dennis 
Published: June 2005

Abstract
Although previously disregarded, polyploidy, and in particular autopolyploidy, is now believed to have played a prominent role in the evolution of plants and animals. We estimated the rate of preferential pairing in second-generation autotetraploid Pacific oysters from gametic frequencies. We found significant levels of preferential pairing in these recently generated autopolyploids, suggesting that genetic variation in standing populations may play a role in meiotic mechanisms of polyploids derived from these populations.
X-Linked Genes Evolve Higher Codon Bias in Drosophila and Caenorhabditis
Authors: Singh Nadia D , Davis Jerel C , Petrov Dmitri A 
Published: June 2005

Abstract
Comparing patterns of molecular evolution between autosomes and sex chromosomes (such as X and W chromosomes) can provide insight into the forces underlying genome evolution. Here we investigate patterns of codon bias evolution on the X chromosome and autosomes in Drosophila and Caenorhabditis. We demonstrate that X-linked genes have significantly higher codon bias compared to autosomal genes in both Drosophila and Caenorhabditis. Furthermore, genes that become X-linked evolve higher codon bias gradually, over tens of millions of years. We provide several lines of evidence that this elevation in codon bias is due exclusively to their chromosomal location and not to any other property of X-linked genes. We present two possible explanations for these observations. One possibility is that natural selection is more efficient on the X chromosome due to effective haploidy of the X chromosomes in males and persistently low effective numbers of reproducing males compared to that of females. Alternatively, X-linked genes might experience stronger natural selection for higher codon bias as a result of maladaptive reduction of their dosage engendered by the loss of the Y-linked homologs.
Conserved Functions of Yeast Genes Support the Duplication, Degeneration and Complementation Model for Gene Duplication
Authors: van Hoof Ambro 
Published: June 2005

Abstract
Gene duplication is often cited as a potential mechanism for the evolution of new traits, but this hypothesis has not been thoroughly tested experimentally. A classical model of gene duplication states that after gene duplication one copy of the gene preserves the ancestral function, while the other copy is free to evolve a new function. In an alternative duplication, divergence, and complementation model, duplicated genes are preserved because each copy of the gene loses some, but not all, of its functions through degenerating mutations. This results in the degenerating mutations in one gene being complemented by the other and vice versa. These two models make very different predictions about the function of the preduplication orthologs in closely related species. These predictions have been tested here for several duplicated yeast genes that appeared to be the leading candidates to fit the classical model. Surprisingly, the results show that duplicated genes are maintained because each copy carries out a subset of the conserved functions that were already present in the preduplication gene. Therefore, the results are not consistent with the classical model, but instead fit the duplication, divergence, and complementation model.
Identification of a Rat Model for Usher Syndrome Type 1B by N-Ethyl-N-nitrosourea Mutagenesis-Driven Forward Genetics
Authors: Smits Bart M G , Peters Theo A , Mul Joram D , Croes Huib J , Fransen Jack A M , Beynon Andy J , Guryev Victor , Plasterk Ronald H A , Cuppen Edwin 
Published: June 2005

Abstract
The rat is the most extensively studied model organism and is broadly used in biomedical research. Current rat disease models are selected from existing strains and their number is thereby limited by the degree of naturally occurring variation or spontaneous mutations. We have used ENU mutagenesis to increase genetic variation in laboratory rats and identified a recessive mutant, named tornado, showing aberrant circling behavior, hyperactivity, and stereotypic head shaking. More detailed analysis revealed profound deafness due to disorganization and degeneration of the organ of Corti that already manifests at the onset of hearing. We set up a single nucleotide polymorphism (SNP)-based mapping strategy to identify the affected gene, revealing strong linkage to the central region of chromosome 1. Candidate gene resequencing identified a point mutation that introduces a premature stopcodon in Myo7a. Mutations in human MYO7A result in Usher syndrome type 1B, a severe autosomal inherited recessive disease that involves deafness and vestibular dysfunction. Here, we present the first characterized rat model for this disease. In addition, we demonstrate proof of principle for the generation and cloning of human disease models in rat using ENU mutagenesis, providing good perspectives for systematic phenotypic screens in the rat.
Quantitative Trait Loci Affecting the Difference in Pigmentation BetweenDrosophila yakubaandD. santomea
Authors: Carbone Mary Anna , Llopart Ana , deAngelis Matthew , Coyne Jerry A , Mackay Trudy F C 
Published: June 2005

AbstractUsing quantitative trait locus (QTL) mapping, we studied the genetic basis of the difference in pigmentation between two sister species of Drosophila: Drosophila yakuba, which, like other members of the D. melanogaster subgroup, shows heavy black pigmentation on the abdomen of males and females, and D. santomea, an endemic to the African island of São Tomé, which has virtually no pigmentation. Here we mapped four QTL with large effects on this interspecific difference in pigmentation: two on the X chromosome and one each on the second and third chromosomes. The same four QTL were detected in male hybrids in the backcrosses to both D. santomea and D. yakuba and in the female D. yakuba backcross hybrids. All four QTL exhibited strong epistatic interactions in male backcross hybrids, but only one pair of QTL interacted in females from the backcross to D. yabuka. All QTL from each species affected pigmentation in the same direction, consistent with adaptive evolution driven by directional natural selection. The regions delimited by the QTL included many positional candidate loci in the pigmentation pathway, including genes affecting catecholamine biosynthesis, melanization of the cuticle, and many additional pleiotropic effects.
High Functional Overlap Between MluI Cell-Cycle Box Binding Factor and Swi4/6 Cell-Cycle Box Binding Factor in the G1/S Transcriptional Program in Saccharomyces cerevisiae
Authors: Bean James M , Siggia Eric D , Cross Frederick R 
Published: June 2005

Abstract
In budding yeast, many genes are induced early in the cell cycle. Induction of these genes has been predominantly attributed to two transcription factors, Swi4-Swi6 (SBF) and Mbp1-Swi6 (MBF). Swi4 and Mbp1 are related DNA-binding proteins with dissimilar target sequences. For most G1/S-regulated genes that we tested in a cdc20 block-release protocol for cell-cycle synchronization, removal of both Swi4 and Mbp1 was necessary and sufficient to essentially eliminate cell-cycle-regulated expression. Detectable SBF or MBF binding sites (SCBs or MCBs) in the promoters or available genome-wide promoter occupancy data do not consistently explain this functional overlap. The overlapping ability of these transcription factors to regulate many promoters with very similar cell-cycle kinetics may provide robustness to the G1/S transcriptional response, but poses a puzzle with respect to promoter-transcription factor specificity. In addition, for some genes, deletion of Mbp1 or Swi4 enhances transcription, suggesting that these factors can also function as transcriptional repressors. Finally, we observe residual G1/S transcriptional regulation in the absence of Swi4 and Mbp1.
Smg1 Nonsense Mutations Do Not Abolish Nonsense-Mediated mRNA Decay in Drosophila melanogaster
Authors: Chen Zhenzhong , Smith Katherine R , Batterham Philip , Robin Charles 
Published: June 2005

Abstract
Smg1 is a key component of nonsense-mediated decay (NMD) in Caenorhabditis elegans and mammals. Here we report that two nonsense alleles of the ortholog of Smg1 do not affect NMD in Drosophila melanogaster.
Geochemical Signatures in Scales Record Stream of Origin in Westslope Cutthroat Trout
Authors: Muhlfeld Clint C. , Marotz Brian , Thorrold Simon R. , FitzGerald Jennifer L. 
Published: June 2005

AbstractWe used laser ablation inductively coupled plasma mass spectrometry (ICP‐MS) to quantify the elemental composition of Mg: Ca, Mn: Ca, Sr: Ca, Ba: Ca, and Pb: Ca ratios in scales from juvenile westslope cutthroat trout Oncorhynchus clarkii lewisi collected from 13 streams in three major drainages (North Fork, South Fork, and Middle Fork) of the upper Flathead River system in Montana during summer 2001 and 2002. We also determined element: Ca levels within natal streams in summer 2001 and 2002. The concentrations of Sr: Ca and Ba: Ca in westslope cutthroat trout scales were highly correlated with those in the water. The multivariate elemental signatures of the scales differed significantly among streams. A forward stepwise discriminant function analysis was used to classify individual fish, first to the drainage of origin and then to the natal stream while considering all 13 streams simultaneously. At the drainage level, cross‐validated classification accuracy was 91% in the Middle Fork, 81% in the North Fork, and 78% in the South Fork; overall accuracy was 82%. Of the fish that were correctly classified at the drainage level, 88% were correctly classified to their natal stream at accuracy levels of 100% in the Middle Fork, 88% in the North Fork, and 80% in the South Fork. Finally, the Mn: Ca, Sr: Ca, and Ba: Ca ratios in westslope cutthroat trout scales were significantly correlated with values in the otoliths of individual fish, suggesting that scales may provide a nonlethal alternative to otoliths as natural markers. Our data indicate that elemental signatures in scales may be used as natural tags to identify the natal stream origin of westslope cutthroat trout in the upper Flathead River system and in other similar freshwater environments. However, future work needs to determine whether elemental signatures are sufficiently stable over time to allow for accurate classification of adult fish after emigration from natal streams.
Early Life History of Blueback Herring and Alewife in the Lower Roanoke River, North Carolina
Authors: Walsh Harvey J. , Settle Lawrence R. , Peters David S. 
Published: June 2005

AbstractSeasonal distribution, abundance, habitat use, hatch dates, growth, and mortality of larval blueback herring Alosa aestivalis and alewife A. pseudoharengus were studied in the Roanoke River watershed, downstream from the Roanoke Rapids Dam in North Carolina. Ichthyoplankton was sampled from man‐made canals, a creek, an oxbow, a flooded bottomland hardwood forest, the main river channel, and along the river's edge. To identify larval clupeids, we developed a dichotomous key for clupeids found in the study area using morphometric, meristic, and pigmentation characters synthesized from the literature. Distribution, abundance, and back‐calculated hatch dates of larvae and eggs were used to describe spawning period, spawning habitat, and nursery habitat. Blueback herring and alewife eggs and larvae were present from early April through late May. Based on the presence of eggs and early‐stage larvae, both species spawned in backwater tributary systems, including flooded bottomland hardwood forests. Our results indicated that blueback herring and alewives used a variety of habitats during early larval stages, though interspecific differences in concentration among habitats were evident. Blueback herring used both lotic (moving water) and lentic (still water) habitats, and alewives were more abundant in lentic habitats. Larval growth varied between years but not between species. Blueback herring growth rates were 0.60 mm/d in 1996 and 0.42 mm/d in 1997 compared with growth rates of 0.65 mm/d in 1996 and 0.41 mm/d in 1997 for alewives. Interspecific and between‐year differences in daily mortality of preflexion blueback herring and alewives (age, 4–8 d) were observed. Blueback herring daily percent mortality in 1996 and 1997 was 99%, while alewife rates decreased from 98% in 1996 to 91% in 1997. Fluctuations in river flow affected habitat use; moderate to high discharge rates increased use of spawning and nursery habitats, and low flows reduced use of spawning habitat.
Novel intercalated nanocomposites of polypropylene, organic rectorite, and poly(ethylene octene) elastomer: Morphology and mechanical properties
Authors: Xiaoyan Ma , Guozheng Liang , Haijun Lu , Hailin Liu , Yun Huang 
Published: June 2005

AbstractThe melt‐blending method was applied to prepare ternary composites of polypropylene (PP), organic rectorite (OREC), and poly(ethylene octene) elastomer (POE) with a constant content of 2 phr (parts per hundred parts of PP) OREC and 5 or 15 phr POE (PRE25 and PRE215, respectively). At the same time, OREC/PP binary composites with a 2 phr loading of OREC (PR2) and POE/PP systems with 5 or 15 phr POE (E5 and E15, respectively) were prepared to investigate synergistic effects of OREC and POE. Scanning electron microscopy was used to study the distribution of OREC and POE in the matrix, X‐ray diffraction (XRD) and transmission electron microscopy were used to investigate the intercalation performance of OREC in the composites, and polarized light microscopy (PLM) was used to observe the crystallization form and crystallite size. The mechanical properties and dynamic mechanical analysis were also measured. The PRE composites exhibited a multiphase structure, that is, a spherical texture of POE, a plate of clay, and a continuous phase of PP; a larger content of POE produced a larger size, a broader distribution of the spherical phase, and a better intercalation performance of the clay. The E systems were binary phases, that is, a spherical texture of POE and a continuous phase of PP. The crystallite size of the PRE composites was finer than that of pure PP according to XRD data, and this was confirmed by PLM. The impact strength and tensile elongation at break of the PRE composites increased dramatically in comparison with those of the PP, PR2, and corresponding E systems, and this indicated that POE and OREC had synergistic toughening and strengthening effects on PP. The storage modulus of PRE was higher than that of pure PP and lower than that of PR2. There were two glass‐transition temperatures in the PRE systems according to the curve of tan δ; they represented those of pure PP and POE, respectively, and indicated that the PRE systems were physical mixtures. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1907–1914, 2005
What policymakers need and must demand from research regarding the employment rate of persons with disabilities
Authors: Silverstein Robert , Julnes George , Nolan Renee 
Published: June 2005

AbstractEnabling persons with disabilities to prepare for and engage in gainful employment has become a priority concern in U.S. society. As a result, federal and state policymakers are adopting employment‐related initiatives designed to enhance the employment rate of persons with disabilities. Policymakers need credible evidence in order to assess and reform these initiatives. This recognized need, however, begs the question of what constitutes ‘credible evidence.’ Of particular concern in the disability policy arena is the debate over the types of conclusion about employment rates that can and cannot be drawn from analyses of national survey data sets. This article connects standard research methodology concepts with the complexities of evaluating disability policy to help stakeholders appreciate the issues involved in this debate. This appreciation can help policymakers (1) recognize unwarranted cause‐and‐effect conclusions based solely on existing national survey data and (2) demand better data and stronger research designs to complement the potential over‐reliance on correlational studies using problematic survey data to estimate policy impacts. To this end, the article concludes with a practical framework with a checklist for assessing the adequacy of research regarding the employment rate of persons with disabilities. Copyright © 2005 John Wiley & Sons, Ltd.
A Cyclopropabenzenylidenethenone (Propadienone) via a New Route to Alkylidenecycloproparenes.
Authors: Halton Brian , Dixon Gareth M. , Jones Carissa S. , Parkin Christopher T. , Veedu Rakesh N. , Bornemann Holger , Wentrup Curt 
Published: June 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Potent and Selective [2‐Imidazol‐1‐yl‐2‐(6‐alkoxy‐naphthalen‐2‐yl)‐1‐methyl‐ethyl] ‐dimethyl‐amines as Retinoic Acid Metabolic Blocking Agents (RAMBAs).
Authors: Mulvihill Mark J. , et al. et al. 
Published: June 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
A New Protocol to Synthesize 1,4‐Dihydropyridines by Using 3,4,5‐Trifluorobenzeneboronic Acid as a Catalyst in Ionic Liquid: Synthesis of Novel 4‐(3‐Carboxyl‐1H‐pyrazol‐4‐yl)‐1,4‐dihydropyridines.
Authors: Sridhar Radhakrishnan , Perumal Paramasivan T. 
Published: June 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
A Practical Approach for Preparation of 2‐[(Dialkylamino)‐methyl]‐4‐aryl‐2H‐phthalazin‐1‐ones via Mannich Reaction of 4‐Aryl‐2H‐phthalazin‐1‐ones.
Authors: Epsztajin Jan , Malinowski Zbigniew , Urbaniak Pawel , Andrijewski Grzegorz 
Published: June 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
3H‐Quinazolin‐4‐ones as a New Calcilytic Template for the Potential Treatment of Osteoporosis.
Authors: Shcherbakova Irina , Balandrin Manuel F. , Fox John , Ghatak Anjan , Heaton William L. , Conklin Rebecca L. 
Published: June 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
2′‐Benzothiazolylthioesters of N‐Substituted α‐Amino Acids: Versatile Intermediates for Synthesis of ACE Inhibitors.
Authors: Singh Girij Pal , Godbole Himanshu M. , Nehate Sagar P. , Mahajan Pravin R. 
Published: June 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Psychologic and social sequelae of secondary lymphedema
Authors: McWayne Janis , Heiney Sue P. 
Published: June 2005

AbstractBACKGROUNDThe psychological and social sequelae of secondary lymphedema (SLE) have been an underrecognized and little‐researched complication of treatment for breast carcinoma. The reported incidence and prevalence of SLE varied widely (0–48%). Reported reasons for the differences are related to the lack of standard diagnostic and universal assessment criteria.METHODSA comprehensive, computerized search was performed. All combinations of the following keywords were used: arm lymphedema, arm swelling, breast cancer, psychological and social, and quality of life (QOL). Eighteen studies were identified.RESULTSThe literature supported the view that SLE leads to psychological and social sequelae. Psychological sequelae included frustration, distress, depression and anxiety. Social sequelae comprised changes in role function, lack of social support and pain and disability. Pain was a significant predictor of psychological and social morbidity. These experiences resulted in diminution of QOL, particularly psychological and social health. This was particularly worrisome because women must attend daily to the precautions and treatments for SLE.CONCLUSIONSResearchers should use psychological and social measures along with physiologic parameters when evaluating the impacts of SLE. Clinicians should work to develop standardized primary prevention programs and limb circumference should be measured at the time of breast carcinoma diagnosis. Gaps in knowledge related to intra/interethnic diversity, poverty, and comorbidities of women with breast carcinoma‐related SLE need to be explored. The combined efforts of researchers and clinicians would reinforce awareness and knowledge for women at risk and provide important baseline data for research and practice. Cancer 2005. © 2005 American Cancer Society.
The clinical use of staging bone scan in patients with breast carcinoma
Authors: Lee Jeong Eon , Park Sung‐Shin , Han Wonshik , Kim Seok Won , Shin Hyuk Jai , Choe Kuk Jin , Oh Seung Keun , Youn Yeo‐Kyu , Noh Dong‐Young , Kim Sung‐Won 
Published: June 2005

AbstractBACKGROUNDUsing the new 2003 American Joint Committee on Cancer (AJCC) staging system, the authors evaluated the usefulness of the staging bone scan in patients with primary breast carcinoma.METHODSThe authors examined 1939 patients with primary breast carcinoma for staging bone scan who were treated at a single institution. Pathologic stage was assigned retrospectively according to the 1988 and the 2003 AJCC staging systems.RESULTSBone metastasis rates were 0.7% (4 of 586) for patients with Stage I disease, 0.7% (5 of 699) for patients with Stage IIA disease, 2.1% (10 of 479) for patients with Stage IIB disease, 4.5% (7 of 154) for patients with Stage IIIA disease, and 10.5% (2 of 19) for patients with Stage IIIB disease according to the 1988 AJCC staging system. The authors found a significant difference in the bone metastasis rate between patients with Stages IIA and IIB disease in the 1988 staging system (P = 0.039). Reevaluating the patients by the 2003 system resulted in significant upstaging, especially for patients with Stage II/III disease. According to the 2003 staging system, bone metastasis rates were 0.7% (4 of 586) for patients with Stage I disease, 0.6% (4 of 648) for patients with Stage IIA disease, 0.6% (2 of 310) for patients with Stage IIB disease, 4.0% (9 of 225) for patients with Stage IIIA disease, 16.7% (2 of 12) for patients with Stage IIIB disease, and 4.4% (7 of 158) for patients with Stage IIIC disease. It was noteworthy that there was a significant difference between Stages IIB and IIIA in the 2003 staging system (P = 0.010).CONCLUSIONSStage reclassification using the new AJCC staging system resulted in upstaging of high‐risk patients, as well as a significant decrease in the bone metastasis rate in patients with Stage IIB breast carcinoma. Considering the cost‐effectiveness of staging bone scan, the data suggested that it was of little value for patients with Stage I and II breast carcinoma, but was highly recommended for patients with worse than Stage III disease by the new 2003 staging system. Cancer 2005. © 2005 American Cancer Society.
Cycloadditions of Aryl‐Substituted 1,2,4‐Triazines with 2‐Cyclopropylidene‐1,3‐dimethylimidazolidine – Zwitterions as Discrete Intermediates
Authors: Ernd Michael , Heuschmann Manfred , Zipse Hendrik 
Published: June 2005

AbstractCycloadditions of 2‐cyclopropylidene‐1,3‐dimethylimidazolidine (1), a strong, electron‐rich C‐nucleophile, with a variety of aryl‐substituted 1,2,4‐triazines occur at temperatures between −100 and +100°, depending on the substitution pattern. At low temperatures, zwitterions, formed by nucleophilic attack of 1 on the triazines, could be detected spectroscopically and, in some cases, isolated. Two types of zwitterions were found: 1) those where the new bond was linked to C(5) of the triazine and which were formed in a reversible dead‐end equilibrium, and 2) those where the new bond was linked either to C(3) or C(6). The latter exhibited the same regiochemistry as the final cycloadducts, and might be intermediates of a two‐step Diels–Alder reaction. Energies and structural characteristics for stationary points in the reaction of monosubstituted triazines with 1 in the gas phase and in CH2Cl2 solution were calculated at the Becke3LYP/6‐311+G(d,p)//Becke3LYP/6‐31G(d) level of theory. Different reaction mechanisms are discussed on the basis of steric, electronic, and solvent effects.