Showing papers by "Washington State University published in 2004"
TL;DR: In this paper, a cross-calibration of U-Pb and Lu-Hf isotopic systems on mineral fractions from the Proterozoic Karlshamn and Sorkka dolerites in Sweden and Finland is presented.
2,146 citations
TL;DR: Results are provided that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure and renal failure in the Oriental white-backed vulture (OWBV) and it is proposed that residues of veterinary diclotenac are responsible for the OWBV decline.
Abstract: The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent Consequently these vultures are now listed as critically endangered by BirdLife International In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarh-Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites Between 2000 and 2003, high annual adult and subadult mortality (5-86%) and resulting population declines (34-95%) (ref 5 and MG, manuscript in preparation) were associated with renal failure and visceral gout Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock We propose that residues of veterinary diclofenac are responsible for the OWBV decline
1,568 citations
TL;DR: A new parameter, qL, is introduced, based on a Stern–Volmer approach using a lake model, which estimates the fraction of open PS II centers and should be a useful parameter for terrestrial plants consistent with a high connectivity of PS II units, whereas some marine species with distinct antenna architecture may require the use of more complex parameters based on intermediate models of the photosynthetic unit.
Abstract: A number of useful photosynthetic parameters are commonly derived from saturation pulse-induced fluorescence analysis. We show, that qP, an estimate of the fraction of open centers, is based on a pure ‘puddle’ antenna model, where each Photosystem (PS) II center possesses its own independent antenna system. This parameter is incompatible with more realistic models of the photosynthetic unit, where reaction centers are connected by shared antenna, that is, the so-called ‘lake’ or ‘connected units’ models. We thus introduce a new parameter, qL, based on a Stern–Volmer approach using a lake model, which estimates the fraction of open PS II centers. We suggest that qL should be a useful parameter for terrestrial plants consistent with a high connectivity of PS II units, whereas some marine species with distinct antenna architecture, may require the use of more complex parameters based on intermediate models of the photosynthetic unit. Another useful parameter calculated from fluorescence analysis is ΦII, the yield of PS II. In contrast to qL, we show that the ΦII parameter can be derived from either a pure ‘lake’ or pure ‘puddle’ model, and is thus likely to be a robust parameter. The energy absorbed by PS II is divided between the fraction used in photochemistry, ΦII, and that lost non-photochemically. We introduce two additional parameters that can be used to estimate the flux of excitation energy into competing non-photochemical pathways, the yield induced by downregulatory processes, ΦNPQ, and the yield for other energy losses, ΦNO.
1,383 citations
TL;DR: A new web-based tool for the prediction of protein phosphorylation sites, DISPHOS (DISorder-enhanced PHOSphorylation predictor, http://www.ist. edu/DISPHOS), which observes that amino acid compositions, sequence complexity, hydrophobicity, charge and other sequence attributes of regions adjacent to phosphate sites are very similar to those of intrinsically disordered protein regions.
Abstract: Reversible protein phosphorylation provides a major regulatory mechanism in eukaryotic cells. Due to the high variability of amino acid residues flanking a relatively limited number of experimentally identified phosphorylation sites, reliable prediction of such sites still remains an important issue. Here we report the development of a new web-based tool for the prediction of protein phosphorylation sites, DISPHOS (DISorder-enhanced PHOSphorylation predictor, http://www.ist.temple. edu/DISPHOS). We observed that amino acid compositions, sequence complexity, hydrophobicity, charge and other sequence attributes of regions adjacent to phosphorylation sites are very similar to those of intrinsically disordered protein regions. Thus, DISPHOS uses position-specific amino acid frequencies and disorder information to improve the discrimination between phosphorylation and non-phosphorylation sites. Based on the estimates of phosphorylation rates in various protein categories, the outputs of DISPHOS are adjusted in order to reduce the total number of misclassified residues. When tested on an equal number of phosphorylated and non-phosphorylated residues, the accuracy of DISPHOS reaches 76% for serine, 81% for threonine and 83% for tyrosine. The significant enrichment in disorder-promoting residues surrounding phosphorylation sites together with the results obtained by applying DISPHOS to various protein functional classes and proteomes, provide strong support for the hypothesis that protein phosphorylation predominantly occurs within intrinsically disordered protein regions.
1,307 citations
TL;DR: The PC-PTSD appears to be a psychometrically sound screen for PTSD with comparable operating characteristtics to other screens for mental disorders.
Abstract: Posttraumatic stress disorder (PTSD) is a frequently unrecognized anxiety disorder in primary care settings. This study reports on the development and operating characteristics of a brief 4-item screen for PTSD in primary care (PC-PTSD). 188 VA primary care patients completed the PC-PTSD, the PTSD Symptom Checklist (PCL) and the Clinician Administered Scale for PTSD (CAPS). The prevalence of PTSD was 24.5%. Signal detection analyses showed that with this base rate, the PC-PTSD had an optimally efficient cutoff score of 3 for both male and female patients. A cutoff score of 2 is recommended when sensitivity rather than efficiency is optimized. The PC-PTSD outperformed the PCL in terms of overall quality, sensitivity, specificity, efficiency, and quality of efficiency. The PC-PTSD appears to be a psychometrically sound screen for PTSD with comparable operating characteristtics to other screens for mental disorders.
1,276 citations
University of Pittsburgh1, State Street Corporation2, University of Chicago3, Monash University4, University of California, Irvine5, University of Maryland, College Park6, Dalhousie University7, University of California, Santa Barbara8, University of Akron9, Washington State University10, Duke University11
TL;DR: A change in approach is needed to determine whether pollen limitation reflects random fluctuations around a pollen–resource equilibrium, an adaptation to stochastic pollination environments, or a chronic syndrome caused by an environmental perturbation.
Abstract: Determining whether seed production is pollen limited has been an area of intensive empirical study over the last two decades. Yet current evidence does not allow satisfactory assessment of the causes or consequences of pollen limitation. Here, we critically evaluate existing theory and issues concerning pollen limitation. Our main conclusion is that a change in approach is needed to determine whether pollen limitation reflects random fluctuations around a pollen–resource equilibrium, an adaptation to stochastic pollination environments, or a chronic syndrome caused by an environmental perturbation. We formalize and extend D. Haig and M. Westoby's conceptual model, and illustrate its use in guiding research on the evolutionary consequences of pollen limitation, i.e., whether plants evolve or have evolved to ameliorate pollen limitation. This synthesis also reveals that we are only beginning to understand when and how pollen limitation at the plant level translates into effects on plant population dynamics...
1,128 citations
TL;DR: In this article, Monte Carlo simulation experiments show that multicollinearity can cause problems under certain conditions, specifically: (1) when multic-linearity is extreme, Type II error rates are generally unacceptably high (over 80%), and sample becomes relatively large, and error rates become negligible.
Abstract: The literature on structural equation models is unclear on whether and when multicollinearity may pose problems in theory testing (Type II errors). Two Monte Carlo simulation experiments show that multicollinearity can cause problems under certain conditions, specifically: (1) when multicollinearity is extreme, Type II error rates are generally unacceptably high (over 80%), (2) when multicollinearity is between 0.6 and 0.8, Type II error rates can be substantial (greater than 50% and frequently above 80%) if composite reliability is weak, explained variance (R2) is low, and sample size is relatively small. However, as reliability improves (0.80 or higher), explained variance R2 reaches 0.75, and sample becomes relatively large, Type II error rates become negligible. (3) When multicollinearity is between 0.4 and 0.5, Type II error rates tend to be quite small, except when reliability is weak, R2 is low, and sample size is small, in which case error rates can still be high (greater than 50%). Methods for detecting and correcting multicollinearity are briefly discussed. However, since multicollinearity is difficult to manage after the fact, researchers should avoid problems by carefully managing the factors known to mitigate multicollinearity problems (particularly measurement error).
1,075 citations
TL;DR: In this paper, a theoretical tourism support model with a series of hypotheses was proposed, and the hypotheses were tested by utilizing a two-stage structural equation modeling approach, which revealed that the host community backing for tourism development is affected directly and/or indirectly by nine determinants of residents' support: the level of community concern, ecocentric values, utilization of tourism resource base, community attachment, the state of the local economy, economic benefits, social benefit, social costs, and cultural benefits.
907 citations
TL;DR: It is shown that the classical mouse mutant luxoid contains a nonsense mutation in the gene encoding Plzf, a transcriptional repressor that regulates the epigenetic state of undifferentiated cells, and this is the first gene shown to be required in germ cells for stem cell self-renewal in mammals.
Abstract: Adult germline stem cells are capable of self-renewal, tissue regeneration and production of large numbers of differentiated progeny. We show here that the classical mouse mutant luxoid affects adult germline stem cell self-renewal. Young homozygous luxoid mutant mice produce limited numbers of normal spermatozoa and then progressively lose their germ line after birth. Transplantation studies showed that germ cells from mutant mice did not colonize recipient testes, suggesting that the defect is intrinsic to the stem cells. We determined that the luxoid mutant contains a nonsense mutation in the gene encoding Plzf, a transcriptional repressor that regulates the epigenetic state of undifferentiated cells, and showed that Plzf is coexpressed with Oct4 in undifferentiated spermatogonia. This is the first gene shown to be required in germ cells for stem cell self-renewal in mammals.
807 citations
Duke University1, University of Minnesota2, Clark University3, University of Graz4, Oregon State University5, University of Gdańsk6, Agriculture and Agri-Food Canada7, National Center for Agricultural Utilization Research8, American Museum of Natural History9, Harvard University10, New York Botanical Garden11, University of British Columbia12, Washington State University13, United States Department of Agriculture14, Free University of Berlin15, University of Tokyo16
TL;DR: This study provides a phylogenetic synthesis for the Fungi and a framework for future phylogenetic studies on fungi and the impact of this newly discovered phylogenetic structure on supraordinal classifications is discussed.
Abstract: Based on an overview of progress in molecular systematics of the true fungi (Fungi/Eumycota) since 1990, little overlap was found among single-locus data matrices, which explains why no large-scale multilocus phylogenetic analysis had been undertaken to reveal deep relationships among fungi. As part of the project ‘‘Assembling the Fungal Tree of Life’’ (AFTOL), results of four Bayesian analyses are reported with complementary bootstrap assessment of phylogenetic confidence based on (1) a combined two-locus data set (nucSSU and nucLSU rDNA) with 558 species representing all traditionally recognized fungal phyla (Ascomycota, Basidiomycota, Chytridiomycota, Zygomycota) and the Glomeromycota, (2) a combined three-locus data set (nucSSU, nucLSU, and mitSSU rDNA) with 236 species, (3) a combined three-locus data set (nucSSU, nucLSU rDNA, and RPB2) with 157 species, and (4) a combined four-locus data set (nucSSU, nucLSU, mitSSU rDNA, and RPB2) with 103 species. Because of the lack of complementarity among single-locus data sets, the last three analyses included only members of the Ascomycota and Basidiomycota. The four-locus analysis resolved multiple deep relationships within the Ascomycota and Basidiomycota that were not revealed previously or that received only weak support in previous studies. The impact of this newly discovered phylogenetic structure on supraordinal classifications is discussed. Based on these results and reanalysis of subcellular data, current knowledge of the evolution of septal features of fungal hyphae is synthesized, and a preliminary reassessment of ascomal evolution is presented. Based on previously unpublished data and sequences from GenBank, this study provides a phylogenetic synthesis for the Fungi and a framework for future phylogenetic studies on fungi.
754 citations
TL;DR: This work proposes community-based efforts to define common criteria and to initiate concerted actions directed towards the release of standard reference materials, construction of consolidated metabolite libraries, and development of metabolite-specific data-management systems.
TL;DR: In this paper, the authors focus on recent findings vis-a-vis titin's molecular spring segments in cardiac titins and discuss new insights regarding the role of titin as a biomechanical sensor and signaling molecule.
Abstract: The sarcomere contains, in addition to thin and thick filaments, a filament composed of the giant protein titin (also known as connectin). Titin molecules anchor in the Z-disc and extend to the M-line region of the sarcomere. The majority of titin’s I-band region functions as a molecular spring. This spring maintains the precise structural arrangement of thick and thin filaments, and gives rise to passive muscle stiffness; an important determinant of diastolic filling. Earlier work on titin has been reviewed before. In this study, our main focus is on recent findings vis-a-vis titin’s molecular spring segments in cardiac titins, including the discovery of fetal cardiac isoforms with novel spring elements. We also discuss new insights regarding the role of titin as a biomechanical sensor and signaling molecule. We will end with focusing on the rapidly growing knowledge regarding titinopathies.
TL;DR: Results have similarly shown immuno-enhancement by nonprovitamin A carotenoids, based either on the relative activity or on the type of immune response affected compared to beta-carotene.
Abstract: Early studies demonstrating the ability of dietary carotenes to prevent infections have left open the possibility that the action of these carotenoids may be through their prior conversion to vitamin A. Subsequent studies to demonstrate the specific action of dietary carotenoids have used carotenoids without provitamin A activity such as lutein, canthaxanthin, lycopene and astaxanthin. In fact, these nonprovitamin A carotenoids were as active, and at times more active, than beta-carotene in enhancing cell-mediated and humoral immune response in animals and humans. Another approach to study the possible specific role of dietary carotenoids has used animals that are inefficient converters of carotenoids to vitamin A, for example the domestic cat. Results have similarly shown immuno-enhancement by nonprovitamin A carotenoids, based either on the relative activity or on the type of immune response affected compared to beta-carotene. Certain carotenoids, acting as antioxidants, can potentially reduce the toxic effects of reactive oxygen species (ROS). These ROS, and therefore carotenoids, have been implicated in the etiology of diseases such as cancer, cardiovascular and neurodegenerative diseases and aging. Recent studies on the role of carotenoids in gene regulation, apoptosis and angiogenesis have advanced our knowledge on the possible mechanism by which carotenoids regulate immune function and cancer.
TL;DR: In this article, a comprehensive theoretical model that integrates psychological/motivational, economics, and processing approaches into a cohesive whole for understanding tourists' information seeking behavior was developed, and the model proposed that for immediate pre-purchase information needs, a consumer is likely to utilize either internal or external sources, or both.
TL;DR: This article examined whether student-teacher relationships predicted two important student behavioral outcomes (academic performance and academic achievement) and found that teacher relationships predicted academic performance and student behavioural outcomes (student academic performance).
Abstract: To explore the significance of social integration in the educational system, this study examined whether student-teacher relationships predicted two important student behavioral outcomes (academic ...
TL;DR: In this article, the authors investigate customer retailer loyalty in the context of multiple channel retailing strategies, and show that multiple channel strategies enhance the portfolio of service outputs provided to the customer, thus enhancing customer satisfaction and ultimately customer retailers loyalty.
TL;DR: Diversity Arrays Technology can be effectively applied to genetic mapping and diversity analyses of barley and is highlighted as a generic technique for genome profiling in the context of molecular breeding and genomics.
Abstract: Diversity Arrays Technology (DArT) can detect and type DNA variation at several hundred genomic loci in parallel without relying on sequence information. Here we show that it can be effectively applied to genetic mapping and diversity analyses of barley, a species with a 5,000-Mbp genome. We tested several complexity reduction methods and selected two that generated the most polymorphic genomic representations. Arrays containing individual fragments from these representations generated DArT fingerprints with a genotype call rate of 98.0% and a scoring reproducibility of at least 99.8%. The fingerprints grouped barley lines according to known genetic relationships. To validate the Mendelian behavior of DArT markers, we constructed a genetic map for a cross between cultivars Steptoe and Morex. Nearly all polymorphic array features could be incorporated into one of seven linkage groups (98.8%). The resulting map comprised ≈385 unique DArT markers and spanned 1,137 centimorgans. A comparison with the restriction fragment length polymorphism-based framework map indicated that the quality of the DArT map was equivalent, if not superior, to that of the framework map. These results highlight the potential of DArT as a generic technique for genome profiling in the context of molecular breeding and genomics.
TL;DR: In this article, a simplified parameterization is proposed based on a representative amplitude, pulse period, and number of significant pulses in the velocity-time history to estimate the peak ground velocity and period of the velocity pulse (Tv) of available forward-directivity motions.
TL;DR: An overview of gonadal steroid modulation of pain and analgesia in animals and humans is presented to describe mechanisms by which males' and females' biology may differentially predispose them to pain and to analgesic effects of drugs and stress.
TL;DR: In this article, the authors proposed a method to reduce microbial load through UV light application as a disinfection medium for food products other than liquids, instead of thermal treatment or application of antimicrobial compounds.
Abstract: Fresh food products can be processed using UV light as a germicidal medium to reduce the food-borne microbial load. Water has been treated with UV light to obtain drinking water for quite some time. Pumpable fruit and vegetable products are generally very suitable for processing by UV light to reduce the microbial load. Today, most of these products are pasteurised to obtain microbiologically safe and nutritious products. However, pasteurisation can change the taste and flavour of such products because of the temperature and processing time. Juices from different sources can be treated by exposure to UV light at different doses. On the other hand, variables such as flow rate, exposure time, type of fruit product, juice colour and juice composition, among other variables, need to be studied to obtain fruit products with reduced microbial load, increased shelf life and adequate sensory and nutritional characteristics. Reduction of microbial load through UV light application as a disinfection medium for food products other than liquids is also being studied. Moreover, UV technology could be a source for pasteurisation of liquids, or disinfection of solid foods as an alternative technology, instead of thermal treatment or application of antimicrobial compounds.
TL;DR: A bifacial model for the functional interaction of PsbS with photosystem II is proposed, based on the extent of qE inhibition in the mutants, photochemical and nonphotochemical quenching processes of Photosystem II were associated with distinct chlorophyll fluorescence life-time distribution components.
TL;DR: In this article, the authors report Yb isotopic data for the purpose of accurately correcting measurements of Lu and Lu/Hf ratios during Multicollector Inductively Coupled Plasma Mass Spectrometer (MC-ICPMS) analysis.
Abstract: [1] We report Yb isotopic data for the purpose of accurately correcting measurements of Lu and Lu/Hf ratios during Multicollector Inductively Coupled Plasma Mass Spectrometer (MC-ICPMS) analysis. The Yb isotopic ratios agree with recent results of Chu et al. [2002] and Amelin and Davis [2004], when corrected for mass fractionation to the same reference values. Protocols for Lu measurement involving simultaneous subtraction of Yb interference and application of a fractionation correction based on Yb are described. It is shown that Lu concentrations and Lu/Hf ratios determined by MC-ICPMS using this methodology are more precise and potentially more accurate than results based on analysis of Lu by Thermal Ionization Mass Spectrometry (TIMS). A number of MC-ICPMS Lu-Hf isotopic analyses of standard rocks and other geological samples, previously analyzed by TIMS, are presented. These document reproducibility of Lu/Hf within 0.2%, where most discrepancies can be assigned to the unknown Lu mass fractionation during TIMS analysis.
TL;DR: In this article, the authors developed an instrument to measure the festival and special event organizers' perceptions of the impacts of festivals and special events on local communities based on the literature and the suggestions of experts in the area.
TL;DR: A developmental testis gene expression time course profiling the expression patterns of ∼36 000 transcripts on the Affymetrix MGU74v2 GeneChip platform at 11 distinct time points was created to gain a greater understanding of the molecular changes necessary for and elicited by the development of the testis.
Abstract: One of the most promising applications of microarrays is the study of changes in gene expression associated with the growth and development of mammalian tissues. The testis provides an excellent model to determine the ability of microarrays to effectively characterize the changes in gene expression as an organ develops from birth to adulthood. To this end, a developmental testis gene expression time course profiling the expression patterns of approximately 36 000 transcripts on the Affymetrix MGU74v2 GeneChip platform at 11 distinct time points was created to gain a greater understanding of the molecular changes necessary for and elicited by the development of the testis. Additionally, gene expression profiles of isolated testicular cell types were created that can aid in the further characterization of the specific functional actions of each cell type in the testis. Statistical analysis of the data revealed 11 252 transcripts (9846 unique) expressed differentially in a significant manner. Subsequent cluster analysis produced five distinct expressional patterns within the time course. These patterns of expression are present at distinct chronological periods during testis development and often share similarities with cell-specific expression profiles. Analysis of cell-specific expression patterns produced unique and characteristic groups of transcripts that provide greater insight into the activities, biological and chronological, of testicular cell types during the progression of spermatogenesis. Further analysis of this time course can provide a distinct and more definitive view into the genes implicated, known and unknown, in the maturation, maintenance, and function of the testis and the integrated process of spermatogenesis.
TL;DR: A theoretical model of resident support for tourism that is based on the social exchange theory was shown to be valid regardless of the distance between residents’ homes and tourism attractions.
TL;DR: In this paper, the authors examine new agricultural cooperative organizational models from an ownership rights perspective and propose a typology of discrete organizational models, in which the traditional cooperative structure and the investor-oriented firm are characterized as polar forms.
Abstract: This article examines new agricultural cooperative organizational models from an ownership rights perspective. The article adopts a definition of ownership rights comprising both residual claim and control rights. We argue that new cooperative organizational models differ in how ownership rights are assigned to the economic agents (members, patrons, and investors) tied contractually to the firm. The article proposes a typology of discrete organizational models, in which the traditional cooperative structure and the investor-oriented firm are characterized as polar forms. The typology also includes five nontraditional models that cooperatives may adopt to ameliorate perceived financial constraints. Agricultural cooperatives have played an important economic role in market
TL;DR: Investigating titin expression in patients with end-stage heart failure resulting from nonischemic dilated cardiomyopathy found changes in titin isoform expression significantly impact diastolic filling by lowering myocardial stiffness and clinical correlations support the relevance of these changes for LV function.
Abstract: Background—The role of the giant protein titin in patients with heart failure is not well established. We investigated titin expression in patients with end-stage heart failure resulting from nonischemic dilated cardiomyopathy, in particular as it relates to left ventricular (LV) myocardial stiffness and LV function. Methods and Results—SDS-agarose gels revealed small N2B (stiff) and large N2BA (compliant) cardiac titin isoforms with a mean N2BA:N2B expression ratio that was significantly (P0.003) increased in 20 heart failure patients versus 6 controls. However, total titin was unchanged. The coexpression ratio was highest in a subsample of patients with an impaired LV relaxation pattern (n7), intermediate in those with pseudonormal filling (n6), and lowest in the group with restrictive filling (n7). Mechanical measurements on LV muscle strips dissected from these hearts (n8) revealed that passive muscle stiffness was significantly reduced in patients with a high N2BA:N2B expression ratio. Clinical correlations support the relevance of these changes for LV function (assessed by invasive hemodynamics and Doppler echocardiography). A positive correlation between the N2BA:N2B titin isoform ratio and deceleration time of mitral E velocity, A wave transit time, and end diastolic volume/pressure ratio was found. These changes affect exercise tolerance, as indicated by the positive correlation between the N2BA:N2B isoform ratio and peak O2 consumption (n10). Upregulated N2BA expression was accompanied by increased expression levels of titin-binding proteins (cardiac ankyrin repeat protein, ankrd2, and diabetes ankyrin repeat protein) that bind to the N2A element of N2BA titin (studied in 13 patients). Conclusions—Total titin content was unchanged in end-stage failing hearts and the more compliant N2BA isoform comprised a greater percentage of titin in these hearts. Changes in titin isoform expression in heart failure patients with dilated cardiomyopathy significantly impact diastolic filling by lowering myocardial stiffness. Upregulation of titin-binding proteins indicates that the importance of altered titin expression might extend to cell signaling and regulation of gene expression. (Circulation. 2004;110:155-162.)
TL;DR: Thermosensitive gold nanoparticles were fabricated by conjugating Au with a thiol-terminated poly(N-isopropylacrylamide) or PPA; this polymer stabilizer exhibits a temperature transition while undergoing a hydrophilic to hydrophobic transformation.
Abstract: Thermosensitive gold nanoparticles were fabricated by conjugating Au with a thiol-terminated poly(N-isopropylacrylamide) or PPA; this polymer stabilizer exhibits a temperature transition while undergoing a hydrophilic to hydrophobic transformation. The introduction of PPA onto gold nanoparticles has sensitized Au nanoparticles with unique temperature dependence. At low temperature (25 °C), the solutions containing PPA-functionalized gold nanoparticles are transparent, whereas higher temperatures (30 °C) lead to opaque suspensions. The thermosensitive property of PPA-functionalized Au nanoparticles is reversible, and the clear−opaque suspensions can be repeated many times.
Kansas State University1, University of California, Davis2, United States Department of Agriculture3, University of Arizona4, Cornell University5, Washington State University6, Iowa State University7, University of Missouri8, University of Minnesota9, North Dakota State University10, Colorado State University11, North Carolina State University12, Texas Tech University13, University of California, Riverside14
TL;DR: The chromosome bin map of ESTs is a unique resource for SNP analysis, comparative mapping, structural and functional analysis, and polyploid evolution, as well as providing a framework for constructing a sequence-ready, BAC-contig map of the wheat genome.
Abstract: Because of the huge size of the common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) genome of 17,300 Mb, sequencing and mapping of the expressed portion is a logical first step for gene discovery. Here we report mapping of 7104 expressed sequence tag (EST) unigenes by Southern hybridization into a chromosome bin map using a set of wheat aneuploids and deletion stocks. Each EST detected a mean of 4.8 restriction fragments and 2.8 loci. More loci were mapped in the B genome (5774) than in the A (5173) or D (5146) genomes. The EST density was significantly higher for the D genome than for the A or B. In general, EST density increased relative to the physical distance from the centromere. The majority of EST-dense regions are in the distal parts of chromosomes. Most of the agronomically important genes are located in EST-dense regions. The chromosome bin map of ESTs is a unique resource for SNP analysis, comparative mapping, structural and functional analysis, and polyploid evolution, as well as providing a framework for constructing a sequence-ready, BAC-contig map of the wheat genome.
TL;DR: It is concluded that PiSLF encodes the pollen self-incompatibility determinant, an S-locus F-box gene of Petunia inflata (Solanaceae), which is consistent with ‘competitive interaction’.
Abstract: Many flowering plants have adopted self-incompatibility mechanisms to prevent inbreeding and promote out-crosses1. In the Solanaceae, Rosaceae and Scrophulariaceae, two separate genes at the highly polymorphic S-locus control self-incompatibility interactions: the S-RNase gene encodes the pistil determinant and the previously unidentified S-gene encodes the pollen determinant2,3,4. S-RNases interact with pollen S-allele products to inhibit the growth of self-pollen tubes in the style. Pollen-expressed F-box genes showing allelic sequence polymorphism have recently been identified near to the S-RNase gene in members of the Rosaceae and Scrophulariaceae5,6,7,8; but until now have not been directly shown to encode the pollen determinant. Here we report the identification and characterization of PiSLF, an S-locus F-box gene of Petunia inflata (Solanaceae). We show that transformation of S1S1, S1S2 and S2S3 plants with the S2-allele of PiSLF causes breakdown of their pollen function in self-incompatibility. This breakdown of pollen function is consistent with ‘competitive interaction’, in which pollen carrying two different pollen S-alleles fails to function in self-incompatibility1,9,10. We conclude that PiSLF encodes the pollen self-incompatibility determinant.