bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel Safflower Germplasm with Increased Saturated Fatty Acid Content
Authors: Hamdan Yamen A. S. , Pérez‐Vich Begoña , Fernández‐Martínez José M. , Velasco Leonardo
Published: January 2009

Safflower (Carthamus tinctorius L.) oil with high concentration of saturated fatty acids has potential applications in the food industry. So far only germplasm with increased stearic acid content (50–120 g kg−1), controlled by alleles at the locus St, has been developed. The objectives of the present research were to evaluate safflower germplasm for saturated fatty acid content, to isolate lines with increased levels of palmitic acid and stearic acid, to study the inheritance of both traits, and to evaluate the feasibility of recombining them. Germplasm evaluation and further selection led to the isolation of the line CR‐50 with increased palmitic acid content (98.2 ± 7.9 g kg−1 vs. 64.0 ± 3.4 g kg−1 in the check) and the line CR‐13 with increased stearic acid content (92.8 ± 9.2 g kg−1 vs. 22.2 ± 3.4 g kg−1 in the check). Inheritance studies including evaluation of F1, F2, and F3 seed generations from crosses with the nuclear male‐sterile line CL1, with conventional fatty acid profile, suggested that increased palmitic acid content was determined by additive alleles at a single locus Pa, whereas stearic acid content was controlled by partially recessive alleles at a single locus, probably St. Recombination of pa and st alleles produced transgressive segregants with 211.3 ± 14.6 g kg−1 saturated fatty acids, compared with 149.6 ± 14.0 g kg−1 in CR‐50, 159.7 ± 8.0 g kg−1 in CR‐13, and 89.3 ± 4.9 in the line CL1. These are the highest levels of saturated fatty acids reported so far in safflower.
Genetic Mapping of Sheath Blight Resistance QTLs within Tropical Japonica Rice Cultivars
Authors: Sharma Arun , McClung Anna M. , Pinson Shannon R. M. , Kepiro Joseph L. , Shank A. Robert , Tabien Rodante E. , Fjellstrom Robert
Published: January 2009

Most commercial cultivars of rice (Oryza sativa L.) are susceptible to sheath blight (SB), a devastating fungal disease causing significant losses in grain yield and quality. There are limited sources of genetic resistance adapted to U.S. growing conditions, and no commercial long grain cultivar of rice is currently available in the United States with a high level of SB resistance. Sheath blight resistance has been reported to be horizontal and quantitative. A population of 279 F2:3 progeny rows derived from a cross between two tropical japonica U.S. rice cultivars, Rosemont (semi‐dwarf, SB susceptible) and Pecos (tall, SB resistant), was used to map SB resistance. Progeny families were evaluated for disease reactions, plant height (PH), and heading date (HD) in replicated field trials for 2 yr and genotyped with 149 simple sequence repeat markers. Correlation analysis between SB ratings with PH and HD showed that both agronomic traits were significantly correlated with SB resistance. Four significant (logarithm of odds ratio ≥ 3.6) quantitative trait loci (QTLs) were identified for SB resistance, with individual effects explaining 5.6 to 33.4% of the total phenotypic variation. Plant height appears to have a direct influence on SB resistance, with QTLs for these traits colocated on chromosome 1. Consistent results across years indicate the stability of the identified QTLs and their potential for improving rice SB resistance using marker‐assisted selection.
Genome‐Wide Reduction of Genetic Diversity in Wheat Breeding
Authors: Fu Yong‐Bi , Somers Daryl J.
Published: January 2009

Public concerns about crop uniformity introduced by modern plant breeding and genetic vulnerability to biotic and abiotic stresses have been one of the major forces driving long‐term efforts in plant germplasm conservation for future food security. However, such concerns have gained little empirical support, as recent molecular diversity analyses of improved crop gene pools did not reveal much reduction from early to recent breeding efforts. We conducted a genome‐wide examination of 75 Canadian hard red spring wheat (Triticum aestivum L.) cultivars released from 1845 to 2004 using 370 simple sequence repeat (or SSR) markers that were widely distributed over all 21 wheat chromosomes. A total of 2280 SSR alleles were detected. Allelic reduction occurred in every part of the wheat genome and a majority of the reduced alleles resided in only a few early cultivars. Significant allelic reduction started in the 1930s. Considering 2010 SSR alleles detected in the 20 earliest cultivars, 38% of them were retained, 18% were new, and 44% were lost in the 20 most recent cultivars. The net reduction of the total SSR variation in 20 recent cultivars was 17%. This clear‐cut evidence not only supports the contention that modern plant breeding reduces the genetic diversity of Canadian wheat, but also underlies the need for conserving wheat germplasm and introducing genetic diversity into wheat breeding.
QTL Analysis of Root Architecture Traits and Low Phosphorus Tolerance in an Andean Bean Population
Authors: Cichy Karen A. , Blair Matthew W. , Galeano Mendoza Carlos H. , Snapp Sieglinde S. , Kelly James D.
Published: January 2009

Tolerance to low P soils is a desirable trait in common bean (Phaseolus vulgarisL.) cultivars grown in acid‐weathered soils. Genetic variability in response to P‐deficient soils exists in the Andean gene pool. G19833, a low P–tolerant indeterminate Andean landrace, has been evaluated for quantitative trait loci (QTL) and tolerance to low P in combination with Mesoamerican parents. Our goal was to expand our understanding of phenotypic traits and QTL from G19833 expressed in an Andean background. An F5:7recombinant inbred line (RIL) population developed from two Andean bean genotypes, G19833 and AND696, a determinate line susceptible to low P soils, was examined under low and high soil P levels in replicated field trials. Phosphorus uptake was reduced by 70% and yield by 60% in low P compared to high P treatments. A linkage map was developed with 11 linkage groups and a total length of 1105 cM. Quantitative trait loci for root growth, seed yield, seed P content, and P use efficiency colocalized near thefingene on linkage group B1. Quantitative trait loci for root growth traits, seed yield, and P uptake colocalized on B11. Quantitative trait loci for root length density (cm cm−3) and root surface area (cm2) did not colocalize with QTL for P uptake. This study indicates that root traits did not play an important role in tolerance to low P soil in an Andean × Andean cross, contrary to previous results with the same P‐efficient Andean parent (G19833) crossed to a Mesoamerican bean genotype.
Development of a PCR Assay and Marker‐Assisted Transfer of Leaf Rust and Stripe Rust Resistance Genes Lr57 and Yr40 into Hard Red Winter Wheats
Authors: Kuraparthy Vasu , Sood Shilpa , See Deven R. , Gill Bikram S.
Published: January 2009

The wheat (Triticum aestivum L.)‐Aegilops geniculata introgression T5DL·5DS‐5MgS(0.95), with stripe rust resistance gene Yr40 and leaf rust resistance gene Lr57, is an effective source of resistance against most isolates of the rust pathogen in Kansas and India. Rust resistance genes Lr57 and Yr40 were transferred to the hard red winter wheat (HRWW) cultivars Jagger and Overley by standard backcrossing and marker‐assisted selection (MAS). PCR‐based cleaved amplified polymorphic sequence (CAPS) markers were developed and used to select backcross F1 plants with rust resistance. Diagnostic polymorphism detected by CAPS marker XLr57/Yr40‐MAS‐CAPS16 was consistent between the resistant source and a set of wheat cultivars selected by the U.S. Wheat Coordinated Agricultural Project. Homozygous BC3F2 plants with rust resistance genes were selected using the Restriction Fragment Length Polymorphisms (RFLP)‐based diagnostic DNA marker polymorphism detected by the wheat grain softness protein (GSP). Deletion of Puroindoline a (Pina‐Mg1) and Puroindoline b (Pinb‐Mg1) gene sequences in the chromosome segment of 5MgS substituting for 5DS of wheat suggests that the backcross derivatives with Lr57/Yr40 can be used to develop hard textured wheats. The HRWW germplasm with Lr57 and Yr40 will provide breeders in the Southern Great Plains with adapted lines having an additional source of resistance that can be used to achieve durability of rust resistance.
Can Changes in Canopy and/or Root System Architecture Explain Historical Maize Yield Trends in the U.S. Corn Belt?
Authors: Hammer Graeme L. , Dong Zhanshan , McLean Greg , Doherty Al , Messina Carlos , Schussler Jeff , Zinselmeier Chris , Paszkiewicz Steve , Cooper Mark
Published: January 2009

Continuous increase in the yield of maize (Zea mays L.) in the U.S. Corn Belt has involved an interaction with plant density. A number of contributing traits and mechanisms have been suggested. In this study we used a modeling approach to examine whether changes in canopy and/or root system architecture might explain the observed trends. A maize crop model was generalized so that changes in canopy and root system architecture could be examined. A layered, diurnal canopy photosynthesis model was introduced to predict consequences of change in canopy architecture. A two‐dimensional root exploration model was introduced to predict consequences of change in root system architecture. Field experiments were conducted to derive model parameters for the base hybrid (Pioneer 3394). Simulation studies for various canopy and root system architectures were undertaken for a range of sites, soils, and densities. Simulated responses to density compared well with those found in field experiments. The analysis indicated that (i) change in root system architecture and water capture had a direct effect on biomass accumulation and historical yield trends; and (ii) change in canopy architecture had little direct effect but likely had important indirect effects via leaf area retention and partitioning of carbohydrate to the ear. The study provided plausible explanations and identified testable hypotheses for future research and crop improvement effort.
Biomass Heterosis as the Basis for Grain and Stover Yield Heterosis in Arid Zone Pearl Millet Hybrids
Authors: Bidinger F. R. , Yadav O.P.
Published: January 2009

Pearl millet [Pennisetum glaucum (L.) R. Br.] single cross hybrids, bred from high‐yielding parental lines in favorable environments, are not well adapted to northwest India's arid zone. The objectives of these experiments were (i) to measure grain and stover yield heterosis in testcrosses of six landrace‐based restorer populations and (ii) to understand how heterosis for biomass and harvest index (HI) affects heterosis for grain and stover yields in crosses of these populations. Six restorer populations and their testcrosses on 10 to 13 A1 male‐sterile lines were evaluated at two arid zone locations of northwest India. Heterosis was calculated as percentage advantage of testcross hybrids over parental restorer population. The range in individual testcross heterosis varied from −3% to +39% for grain yield and from −22% to +17% for stover yield. Variation in biomass heterosis accounted for 55% of the variation in grain yield heterosis and 84% of the variation in stover yield heterosis. Harvest index heterosis accounted for 38% of variation in grain yield heterosis and 13% of stover yield heterosis with a positive heterosis in HI resulting in negative heterosis in stover yield. The testcrosses with the highest biomass heterosis for each restorer population achieved 20% biomass heterosis level (combined with a mean 12% heterosis in HI), resulting in 32% grain yield heterosis and 18% stover yield heterosis. We concluded that heterosis for biomass was the major determinant of grain and stover yield heterosis in pearl millet.
Trait‐Specific Improvement of a Cytoplasmic Male‐Sterile Line Using Molecular Marker‐Assisted Selection in Rice
Authors: Gao F. Y. , Lu X. J. , Wang W. M. , Sun S. S. , Li Z. H. , Li H. J. , Ren G. J.
Published: January 2009

To specifically improve preharvest sprouting (PHS) and amylose content (AC) in the cytoplasmic male‐sterile (CMS) line G46A, two simple sequence repeat (SSR) markers, RM3754 and RM447, that are closely linked to qPSR8, a major quantitative trait locus for PHS, were adopted to select for reduced PHS; SSR marker 484/485, which is tightly linked to the waxy gene, was used to select for AC. In the backcross progenies with G46B, the maintainer of G46A, as recurrent parent and ‘Lemont’ as donor parent, most plants with a homozygous Lemont allele at both RM3754 and RM447 showed good PHS resistance. Amylose content in the progeny of G46B/Lemont was significantly related to a difference in alleles at the 484/485 locus. Based on agronomic trait performance and evaluation for PHS and AC, 28 elite lines obtained from the BC3F5 generation were then used in further backcross schemes to breed improved CMS lines. Subsequently, two improved CMS lines showed traits similar to G46A but with improved PHS resistance and intermediate AC.
Phospholipase A2 Activity during Cold Acclimation of Wheat
Authors: Skinner Daniel Z.
Published: January 2009

The temperature lethal to 50% of the plants (LT50) and phospholipase A2 (PLA2) activity levels were investigated in three wheat (Triticum aestivum L.) lines that had been cold acclimated 0 to 5 wks at 3°C. In the cold‐tolerant winter wheat ‘Eltan’, the level of PLA2 activity increased significantly during the first week of cold acclimation, but activity did not increase until the second week of acclimation in cold‐sensitive winter wheat Oregon Feed Wheat #5 and spring wheat ‘Louise’. The PLA2 activity declined in all lines by the end of 4 wks of acclimation. The LT50 decreased (greater freezing tolerance) during the time that PLA2 levels were elevated and then increased concomitant with decreased PLA2 activity. A chilling treatment of −5°C for 45 min resulted in elevated PLA2 activity in nonacclimated Eltan, as well as in all three wheat lines that had been acclimated for 1 wk, but not in plants that had been acclimated for more than 1 wk. These results suggest that PLA2 activity is involved in response to cold temperature in wheat, but the intrinsic level of freezing tolerance and the level of acclimation reached by the plants mediates its activity.
Bulked Segregant Analysis Using the GoldenGate Assay to Locate the Rpp3 Locus that Confers Resistance to Soybean Rust in Soybean
Authors: Hyten David L. , Smith James R. , Frederick Reid D. , Tucker Mark L. , Song Qijian , Cregan Perry B.
Published: January 2009

Few resistance loci to soybean rust (SBR), caused by Phakopsora pachyrhizi Syd., have been genetically mapped and linked to molecular markers that can be used for marker assisted selection. New technologies are available for single nucleotide polymorphism (SNP) genotyping that can be used to rapidly map traits controlled by single loci such as resistance to SBR. Our objective was to demonstrate that the high‐throughput SNP genotyping method known as the GoldenGate assay can be used to perform bulked segregant analysis (BSA) to find candidate regions to facilitate efficient mapping of a dominant resistant locus to SBR designated Rpp3 We used a 1536 SNP GoldenGate assay to perform BSA followed by simple sequence repeat (SSR) mapping in an F2 population segregating for SBR resistance conditioned by Rpp3 A 13‐cM region on linkage group C2 was the only candidate region identified with BSA. Subsequent F2 mapping placed Rpp3 between SSR markers BARC_Satt460 and BARC_Sat_263 on linkage group C2 which is the same region identified by BSA. These results suggest that the GoldenGate assay was successful at implementing BSA, making it a powerful tool to quickly map qualitative traits since the GoldenGate assay is capable of screening 1536 SNPs on 192 DNA samples in three days.
Examination of Macrolevel Annual Safety Performance Measures for Virginia
Authors: Kweon Young-Jun
Published: January 2009

Municipal, state, and federal agencies in the United States that are responsible for traffic safety have used crash rates such as fatalities per 100 million vehicle miles traveled (VMT) as traffic safety performance measures. However, the appropriateness of using such rates as performance measures has not been examined empirically, although the rates have been made public. This study examined 20 candidate crash rates (e.g., fatalities per million population and injury crashes per million registered vehicles) for an annual safety performance measure for Virginia by using autoregressive error models and empirical data from 1971 through 2006. The study found that the injury rate per driver and the crash rate per VMT seem appropriate as, respectively, long-term (1971 to 2006) and shorter-term (1995 to 2006) safety performance measures for Virginia. Statistical uncertainty should be considered when these rates are used to measure safety performance.
New Criteria for Evaluating Methods of Identifying Hot Spots
Authors: Cheng Wen , Washington Simon
Published: January 2009

Identification of hot spots, also known as the sites with promise, black spots, accident-prone locations, or priority investigation locations, is an important and routine activity for improving the overall safety of roadway networks. Extensive literature focuses on methods for hot spot identification (HSID). A subset of this considerable literature is dedicated to conducting performance assessments of various HSID methods. A central issue in comparing HSID methods is the development and selection of quantitative and qualitative performance measures or criteria. The authors contend that currently employed HSID assessment criteria–namely false positives and false negatives–are necessary but not sufficient, and additional criteria are needed to exploit the ordinal nature of site ranking data. With the intent to equip road safety professionals and researchers with more useful tools to compare the performances of various HSID methods and to improve the level of HSID assessments, this paper proposes four quantitative HSID evaluation tests that are, to the authors’ knowledge, new and unique. These tests evaluate different aspects of HSID method performance, including reliability of results, ranking consistency, and false identification consistency and reliability. It is intended that road safety professionals apply these different evaluation tests in addition to existing tests to compare the performances of various HSID methods, and then select the most appropriate HSID method to screen road networks to identify sites that require further analysis. This work demonstrates four new criteria using 3 years of Arizona road section accident data and four commonly applied HSID methods [accident frequency ranking, accident rate ranking, accident reduction potential, and empirical Bayes (EB)]. The EB HSID method reveals itself as the superior method in most of the evaluation tests. In contrast, identifying hot spots using accident rate rankings performs the least well among the tests. The accident frequency and accident reduction potential methods perform similarly, with slight differences explained. The authors believe that the four new evaluation tests offer insight into HSID performance heretofore unavailable to analysts and researchers.
Derivation and Validation of New Simulation-Based Surrogate Safety Measure
Authors: Ozbay Kaan , Yang Hong , Bartin Bekir , Mudigonda Sandeep
Published: January 2009

Traffic safety evaluation is one of the most important processes in analyzing transportation systems performance. Traditional methods like statistical models and before-after comparisons have many drawbacks, such as limited time periods, sample size problems, and reporting errors. The advancement of traffic conflict techniques combined with microsimulation offers a potentially innovative way for conducting safety assessment of traffic systems even before safety improvements are implemented. In this paper, simulation-based safety studies are reviewed, and a modified simulation-based surrogate safety measure and a new simulation-based surrogate safety measure that can capture the probability of collisions, as well as the severity of these potential collisions, are proposed. Conceptual and computational logic of the proposed surrogate safety indicators are described in detail. These surrogate safety indices are initially proposed for link-based analysis and should not be used for other purposes, such as intersection safety assessment, without further enhancements, and the use of these indices should be limited to the analysis of linear conflicts. In addition, these link-based indices are extended to be able to conduct aggregate networkwide safety assessments. The proposed indices are validated by means of a well-calibrated traffic simulation model of a section of the New Jersey Turnpike and real accident data from the same section. Preliminary results indicate a strong relationship between the proposed surrogate safety measures and real accident data. Further research is needed to investigate these new surrogate safety indices under different locations and traffic conditions.
Hit-and-Run Crashes
Authors: Kim Karl , Pant Pradip , Yamashita Eric Y.
Published: January 2009

In this paper, an innovative mathematical tool, rough set analysis (RSA), combined with logistic regression modeling, is used to understand the key factors associated with hit-and-run collisions in Hawaii. After a description of the nature of the problem in Hawaii and some background on the RSA, the methods are applied to a comprehensive database of police-reported accidents over the period 2002 to 2005. RSA is used to extract the key determinants of hit-and-run collisions. With the information from the RSA, a logistic regression model is built to explain the key factors associated with hit-and-run crashes in Hawaii. Factors such as being (a) a male, (b) a tourist, and (c) intoxicated and driving a stolen vehicle are strong predictors of hit-and-run crashes. In addition to the obvious human factors associated with these crashes, there are interesting roadway features, such as horizontal alignment, weather, and lighting, that are also significantly related to hit-and-run crashes. Some suggestions for reducing hit-and-run crashes as well as opportunities for additional research are identified.
Effect of Increases in Speed Limits on Severities of Injuries in Accidents
Authors: Malyshkina Nataliya V. , Mannering Fred
Published: January 2009

The influence of speed limits on roadway safety has been a subject of continuous debate in the state of Indiana and nationwide. In Indiana, highway-related accidents result in about 900 fatalities and 40,000 injuries annually and place an incredible social and economic burden on the state. Still, speed limits posted on highways and other roads are routinely exceeded as drivers try to balance safety, mobility (speed), and the risks and penalties associated with law enforcement efforts. The combined issue of speed limits and safety issue has been a matter of considerable concern in Indiana since the state raised its speed limits on rural Interstates and selected multilane highways on July 1, 2005. In this paper, the influence of the posted speed limit on the severity of vehicle accidents is studied through Indiana accident data from 2004 (the year before speed limits were raised) and 2006 (the year after speed limits were raised on rural Interstates and some multilane non-Interstate routes). Statistical models estimated the injury severity of different types of accidents on various roadway classes. The results of the model estimations showed that, for the speed limit ranges currently used, speed limits did not have a statistically significant effect on the severity of accidents on Interstate highways. However, for some non-Interstate highways, higher speed limits were found to be associated with higher accident severities, suggesting that future speed limit changes, on non-Interstate highways in particular, need to be carefully assessed on a case-by-case basis.
Gastrointestinal Microflora and Mucins May Play a Critical Role in the Development of 5-Fluorouracil-Induced Gastrointestinal Mucositis
Authors: Stringer Andrea M. , Gibson Rachel J. , Logan Richard M. , Bowen Joanne M. , Yeoh Ann S. J. , Hamilton Juliette , Keefe Dorothy M. K.
Published: January 2009

5-Fluorouracil (5-FU) is a commonly used chemotherapy agent in clinical oncology practice. Two of its major side effects are mucositis and diarrhoea. The structure of mucins offers mucosal protection, and allows maintenance of intestinal flora by providing attachment sites and preventing bacterial overgrowth and/or penetration. The aim of this study was to investigate changes in mucin secretion and microflora following treatment with 5-FU. Female DA rats were given a single 150 mg/ kg i.p. dose of 5-FU. Rats were killed at various time points after treatment. Control rats received no treatment. Jejunum, colon and faecal samples were collected. Standard microbiological culture techniques were used to identify bacteria, and real-time PCR was used to quantify bacteria in faecal samples. Goblet cells and cavitated goblet cells (having undergone mucus exocytosis) were also counted. Statistical analysis was carried out using Kruskal-Wallis test, a non-parametric method of testing equality of group medians. Following treatment with 5-FU, we showed decreases in Clostridium spp., Lactobacillus spp. and Streptococcus spp., and an increase in Escherichia spp. in the jejunum. In the colon, 5-FU caused decreases in Enterococcus spp., Lactobacillus spp. and Streptococcus spp. Real-time PCR of faecal samples showed decreasing trends in Lactobacillus spp. and Bacteroides spp., and an increasing trend in E. coli. Significant increases ( P < 0.05) were seen in Clostridium spp. and Staphylococcus spp. at 24 h. Goblet cell numbers decreased significantly in the jejunum from 24–72 h, with a significant increase in the percentage of cavitated goblet cells. In conclusion, 5-FU treatment causes significant changes in intestinal flora and mucin secretion in rats. These changes could result in systemic effects and, in particular, may contribute to the development of chemotherapy-induced mucositis.
Grafts of Porcine Small Intestinal Submucosa with Cultured Autologous Oral Mucosal Epithelial Cells for Esophageal Repair in a Canine Model
Authors: Wei Ren-Qian , Tan Bo , Tan Mei-Yun , Luo Jing-Cong , Deng Li , Chen Xiao-He , Li Xiu-Qun , Zuo Xiao , Zhi Wei , Yang Peng , Xie Hui-Qi , Yang Zhi-Ming
Published: January 2009

The acellular porcine small intestinal submucosa (SIS) has been successfully used for esophagoplasty. However, it does not lead to a complete epithelialization in a canine model. A cellular component may be required for better reconstruction. The present study was undertaken to investigate the feasibility and effectiveness of the combination of SIS and autologous oral mucosal epithelial cells (OMECs) for esophageal reconstruction. The OMECs harvested from beagle dogs were cultured and propagated, and the 3rd passage cells were seeded on a single-layer SIS. Male beagle dogs were subjected to surgical resection to produce cervical esophageal defects (5 cm in length, 180° in range). SIS with or without OMECs was patched on the esophageal defects. Barium esophagram, immunohistochemistry, and histology were performed to evaluate the therapeutic effectiveness. Four weeks after surgery, the histological examination showed a complete re-epithelialization and almost no inflammation in the SIS with OMECs group. But in the SIS group, only a partial epithelialization was observed along with inflammation. Eight weeks after surgery, the squamous epithelium was found to cover the entire graft surface in both groups; however, the muscular regeneration was observed in the SIS with OMECs, but not in the SIS group. The graft of SIS combined with autologous OMECs promotes re-epithelialization and muscular regeneration. It is an effective alternative method for esophageal repair.
A Survey on Star Identification Algorithms
Authors: Spratling Benjamin B. , Mortari Daniele
Published: January 2009

The author surveys algorithms used in star identification, commonly used in star trackers to determine the attitude of a spacecraft. Star trackers are a staple of attitude determination systems for most types of satellites. The paper covers: (a) lost-in-space algorithms (when no a priori attitude information is available), (b) recursive algorithms (when some a priori attitude information is available), and (c) non-dimensional algorithms (when the star tracker calibration is not well-known). The performance of selected algorithms and supporting algorithms are compared.
Special Issue on Marine Toxins
Authors: Mayer Alejandro M.S.
Published: January 2009

The special issue on Marine Toxins of the Open Access journal Marine Drugs (ISSN 1660-3397, http://www.mdpi.com/journal/marinedrugs/) presents twenty four contributions which were received from distinguished investigators currently working in Canada, China, France, Germany, Iran, Italy, Japan, Portugal, Russian Federation, Slovenia, South Africa, Spain, and the United States. The reviews and research articles provide the interested reader with a global view of marine toxins research during 2007-2008. [...]
Capture of Escherichia coli O157:H7 Using Immunomagnetic Beads of Different Size and Antibody Conjugating Chemistry
Authors: Tu Shu-I , Reed Sue , Gehring Andrew , He Yiping , Paoli George
Published: January 2009

Immunomagnetic beads (IMB) were synthesized using anti-Escherichia coli O157 antibodies and magnetic beads of two different sizes (1 mm and 2.6 to 2.8 mm) that contained a streptavidin coating, activated carboxyl groups or tosylated surfaces. The synthesized IMB, together with a commercially available IMB, were used to capture different strains of E. coli O157:H7 and E. coli O157:NM. The E. coli capture was measured by the time resolved fluorescence (TRF) intensity using a sandwich assay which we have previously demonstrated of having a sensitivity of 1 CFU/g after 4.5 hour enrichment [1]. The analyses of measured TRF intensity and determined antibody surface concentration indicated that larger beads provided higher response signals than smaller beads and were more effective in capturing the target of interest in pure culture and ground beef. In addition, while each type of IMB showed different favorable capture of E. coli O157:H7, streptavidin-coated IMB elicited the highest response, on average. Streptavidin-coated IMB also provided an economic benefit, costing less than $0.50 per assay. The results could be used to guide the proper choice of IMB for applications in developing detection processes for E. coli O157:H7.
New Approach Toward Fast Response Light‐Emitting Electrochemical Cells Based on Neutral Iridium Complexes via Cation Transport
Authors: Kwon Tae‐Hyuk , Oh Yong Ho , Shin Ik‐Soo , Hong Jong‐In
Published: January 2009

Here, a new method is presented to increase the turn‐on time and stability of light‐emitting electrochemical cells (LECs). To this end, a neutral iridium complex (5) containing a pendant Na+ ion that is generally known to have a faster mobility in the solid film than bulky anions is introduced, instead of the classic ionic transition metal complex (iTMC) with counter anion (7). Synthesis, photophysical and electrochemical studies of these complexes are reported. In the device configuration of ITO/5 or 7+PEO (polyethylene oxide) (100–110 nm)/Au, as the voltage increases, complex 5 emits red light at −3.6 V while complex 7 appears at –5.6 V, although their electrochemical and photophysical gap are similar. Furthermore, at constant voltage, –3 V, the turn‐on time of complex 5 was less than 0.5 min, which is a 60‐fold faster turn‐on time compared to the iTMC (7) with PF6−. These results are presumably due to the faster delivery of the Na+ ions to the electrode compared to PF6− ions. Also, the device lifetime of complex 5 exhibits a six‐fold increase in stability and a three‐fold shorter time to reach maximum brightness at constant bias compared to the device made with complex 7.
Stacking the Nanochemistry Deck: Structural and Compositional Diversity in One‐Dimensional Photonic Crystals
Authors: Bonifacio Leonardo D. , Lotsch Bettina V. , Puzzo Daniel P. , Scotognella Francesco , Ozin Geoffrey A.
Published: January 2009

One‐dimensional photonic structures, known as Bragg stacks or Bragg reflectors or Bragg mirrors, represent a well‐developed subject in the field of optical science. However, because of a lack of dynamic tunability and their dependence on complex top‐down techniques for their fabrication, they have received little attention from the materials science community. Herein, we present recent and ongoing developments on the way to functional one‐dimensional photonic structures obtained from simple bottom‐up techniques. We focus on the versatility of this new approach, which allows the incorporation of a wide range of materials into photonic structures.
Heritability of neurocognitive traits in familial schizophrenia
Authors: Husted Janice A. , Lim Sooyeol , Chow Eva W.C. , Greenwood Celia , Bassett Anne S.
Published: January 2009

Neurocognitive deficits are considered promising endophenotypes for gene discovery in schizophrenia. Understanding the heritability and genetic inter‐relationships of neurocognitive traits could support their use as alternatives to diagnosis. Participants were 85 adults from 17 multiplex Canadian families with familial schizophrenia linked to 1q23 who had neurocognitive testing results available. Heritability of 13 standard measures assessing motor skills, processing speed, verbal, and visuospatial memory, attention/working memory, executive functioning, and IQ was estimated using variance component models and SOLAR software. We then investigated bivariate relationships between those variables found to be heritable. IQ showed the highest heritability (h2 = 0.64–0.74) and seven other neurocognitive measures, reflecting immediate and delayed verbal memory, attention/working memory, delayed visual memory, processing speed and motor skills, showed significant heritability (h2 = 0.31–0.62) under one or more of the models assessed. A schizophrenia diagnostic covariate was significant (P < 0.0001) for all heritable variables. Bivariate analyses suggested that memory‐IQ and visuomotor‐processing speed formed two groups of heritable traits. The results provide further evidence of the heritability of selected neurocognitive measures, and their relationship to schizophrenia and underlying genetic architecture. Composite measures of memory or processing speed may be heritable phenotypes useful for studies of neurocognition. © 2009 Wiley‐Liss, Inc.
Reaction of a Metallamacrocycle Leading to a Mercury(II)⋅⋅⋅Palladium(II)⋅⋅⋅Mercury(II) Interaction
Authors: Sharma Sagar , Baligar Rajesh S. , Singh Harkesh B. , Butcher Ray J.
Published: January 2009

Metallophile Wechselwirkung: Ein aus Bis(o‐formylphenyl)quecksilber und 1,2‐Phenylendiamin erhaltener, 22‐gliedriger Makrocyclus reagiert mit Palladium(II) unter Spaltung des Makrocyclus und gleichzeitiger Bildung eines Trimetallkomplexes (siehe Bild; die Phenylringe sind nur ausschnittsweise gezeigt). Die Art der HgII⋅⋅⋅PdII⋅⋅⋅HgII‐Wechselwirkung wurde in theoretischen Studien untersucht.

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Formation of Patches on 3D SAMs Driven by Thiols with Immiscible Chains Observed by ESR Spectroscopy
Authors: Gentilini Cristina , Franchi Paola , Mileo Elisabetta , Polizzi Stefano , Lucarini Marco , Pasquato Lucia
Published: January 2009

Mehr als nur Streifen: Die außergewöhnliche Lipophobie von perfluorierten Ketten löst in dreidimensionalen selbstorganisierten Monoschichten von amphiphilen Alkylthiolaten die Bildung „sternfömiger“ Strukturen (oder Flecken) aus. Diese Strategie führte zur ersten wasserlöslichen kompartimentierten Monoschicht auf einem Goldkern.

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Evidence for a Stereoelectronic Effect in Human Oxygen Sensing
Authors: Loenarz Christoph , Mecinović Jasmin , Chowdhury Rasheduzzaman , McNeill Luke A. , Flashman Emily , Schofield Christopher J.
Published: January 2009

Warum sind PHDs spezifisch: Die Hydroxylierung von Prolin in trans‐4‐Stellung verläuft beim Transkriptionsfaktor HIF unter stereochemischer Retention. Studien mit Substratanaloga zeigen, wie das Von‐Hippel‐Lindau‐Tumorsuppressorprotein (pVHL) und als Sauerstoffsensoren wirkende Hydroxylasen (PHDs) eine Spezifität für in einer Proteinsequenz befindliche Hydroxyprolyl/Prolyl‐Reste der C4‐exo/endo‐Prolyl‐Konformationen ausbilden.

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STM Insight into Hydrogen‐Bonded Bicomponent 1 D Supramolecular Polymers with Controlled Geometries at the Liquid–Solid Interface
Authors: Ciesielski Artur , Schaeffer Gaël , Petitjean Anne , Lehn Jean‐Marie , Samorì Paolo
Published: January 2009

Supramolekulare Zweikomponentenpolymere aus sich abwechselnden Molekülen, die über sechs H‐Brücken verbunden sind, wurden durch STM an der Fest‐flüssig‐Grenzfläche nachgewiesen. Die geometrischen Merkmale der 1D‐Architekturen ließen sich über die Verwendung zweier unterschiedlich starrer verknüpfender Moleküle einstellen; es entstanden entweder lineare (links) oder Zickzackmotive (rechts).

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Iridium‐Catalyzed Reactions of Trifluoromethylated Compounds with Alkenes: A CH Bond Activation α to the Trifluoromethyl Group
Authors: Guo Yong , Zhao Xiaming , Zhang Dazhi , Murahashi Shun‐Ichi
Published: January 2009

Atomökonomische Katalyse: Die Verwendung von Iridium‐ oder Rutheniumkatalysatoren für die C‐H‐Bindungsaktivierung ermöglicht die Addition trifluormethylierter Verbindungen an Alkene (siehe Schema). Diese atomökonomische Reaktion verläuft unter neutralen Reaktionsbedingungen und selbst bei hoher Temperatur ohne Bildung unerwünschter Defluorierungsprodukte.

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A Bistable Poly[2]catenane Forms Nanosuperstructures
Authors: Olson Mark A. , Braunschweig Adam B. , Fang Lei , Ikeda Taichi , Klajn Rafal , Trabolsi Ali , Wesson Paul J. , Benítez Diego , Mirkin Chad A. , Grzybowski Bartosz A. , Stoddart J. Fraser
Published: January 2009

Side‐chain poly[2]catenanes at the click of a switch! A bistable side‐chain poly[2]catenane has been synthesized and found to form hierarchical self‐assembled hollow superstructures of nanoscale dimensions in solution. Molecular electromechanical switching (see picture) of the material is demonstrated, and the ground‐state equilibrium thermodynamics and switching kinetics are examined as the initial steps towards processible molecular‐based electronic devices and nanoelectromechanical systems.

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Formation of Patches on 3D SAMs Driven by Thiols with Immiscible Chains Observed by ESR Spectroscopy
Authors: Gentilini Cristina , Franchi Paola , Mileo Elisabetta , Polizzi Stefano , Lucarini Marco , Pasquato Lucia
Published: January 2009

Beyond stripes: The extreme lipophobicity of perfluorinated chains attached to amphiphilic thiolates triggers the formation of “stars” (or patches) surrounded by amphiphilic alkylthiolates in three‐dimensional self‐assembled monolayers. This strategy led to the first example of a water‐soluble multicompartment monolayer wrapped around a gold core.

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Shape‐Selective Interception by Hydrocarbons of the O2‐Derived Oxidant of a Biomimetic Nonheme Iron Complex
Authors: Mukherjee Anusree , Martinho Marlène , Bominaar Emile L. , Münck Eckard , Que Lawrence
Published: January 2009

Picky ferryl: The complex [Fe(Tp)(BF)] (Tp=hydrotris(3,5‐diphenylpyrazolyl)borate; BF=benzoylformate) reacts with O2 to generate an oxidant (see picture; O red, pink; Fe yellow; N blue; C gray; H white) that oxidizes added hydrocarbons shape‐selectively. Discrimination derives from a cleft formed by two phenyl groups of the Tp ligand, favoring oblate spheroidal substrates.

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Pregnancy in patients with ankylosing spondylitis: Do regulatory T cells play a role?
Authors: Förger Frauke , Villiger Peter M. , Østensen Monika
Published: January 2009

Objective

To investigate the numerical and functional changes of CD4+CD25high regulatory T (Treg) cells during pregnancy and postpartum in patients with ankylosing spondylitis (AS).

Methods

The frequency of CD4+CD25high T cells was determined by flow cytometry in 10 pregnant and 5 nonpregnant patients with AS as well as in 14 pregnant and 4 nonpregnant healthy controls. Pregnant individuals were investigated at the third trimester and 8 weeks postpartum. Treg cells and CD4+CD25− effector T (Teff) cells separated by fluorescence‐activated cell sorting were stimulated with anti‐CD3 and anti‐CD28 monoclonal antibodies, alone or in coculture, to investigate proliferation and cytokine secretion.

Results

The frequency of CD4+CD25high Treg cells was significantly higher during pregnancy than postpartum in both healthy control subjects and patients with AS. In contrast to Treg cells in healthy pregnant women, Treg cells in pregnant women with AS secreted only small amounts of interleukin‐10 and showed lower suppression of tumor necrosis factor α and interferon‐γ secretion by CD4+CD25− Teff cells. At the postpartum time point, proinflammatory cytokine levels in the Treg/Teff cell cocultures and Teff cell monocultures were significantly higher in patients with AS than in healthy controls.

Conclusion

Pregnancy influenced the expansion and cytokine secretion of Treg cells in both patients with AS and control subjects. However, the Treg cells of pregnant patients with AS failed to support an antiinflammatory cytokine milieu, thereby possibly contributing to the persistent disease activity of AS during pregnancy.
Serum uric acid level as an independent risk factor for all‐cause, cardiovascular, and ischemic stroke mortality: A chinese cohort study
Authors: Chen Jiunn‐Horng , Chuang Shao‐Yuan , Chen Hsin‐Jen , Yeh Wen‐Ting , Pan Wen‐Harn
Published: January 2009

Objective

The association between hyperuricemia and cardiovascular events has been documented in high‐risk groups, but is still undetermined in general populations, especially Chinese. This study assessed the temporal association between serum uric acid level, hyperuricemia, and cardiovascular mortality.

Methods

A prospective cohort study of 41,879 men and 48,514 women ages ≥35 years was conducted using data from the MJ Health Screening Centers in Taiwan. Mortality from all causes, total cardiovascular disease (CVD), ischemic stroke, congestive heart failure, hypertensive disease, and coronary heart disease were compared according to increasing serum uric acid levels.

Results

A total of 1,151 (21.2%) events of 5,427 total deaths were ascribed to CVD (mean followup 8.2 years). Hazard ratios (HRs) for hyperuricemia (serum uric acid level >7 mg/dl) were estimated with Cox regression model after adjusting for age, sex, body mass index, cholesterol, triglycerides, diabetes, hypertension, heavy cigarette smoking, and frequent alcohol consumption. In all patients, HRs were 1.16 (P < 0.001) for all‐cause mortality, 1.39 (P < 0.001) for total CVD, and 1.35 (P = 0.02) for ischemic stroke. In subgroup analysis, the HRs for cardiovascular risk remained significant in patients with hypertension (1.44, P < 0.001) and in patients with diabetes (1.64, P < 0.001). In addition, in a low metabolic risk subgroup, the HRs for all‐cause mortality and total cardiovascular morbidity were 1.24 (P = 0.02) and 1.48 (P = 0.16), respectively.

Conclusion

Hyperuricemia was an independent risk factor of mortality from all causes, total CVD, and ischemic stroke in the Taiwanese general population, in high‐risk groups, and potentially in low‐risk groups.
Incidence and clinical predictors of psoriatic arthritis in patients with psoriasis: A population‐based study
Authors: Wilson Floranne C. , Icen Murat , Crowson Cynthia S. , McEvoy Marian T. , Gabriel Sherine E. , Kremers Hilal Maradit
Published: January 2009

Objective

To determine the incidence and disease‐specific predictors of clinically recognized psoriatic arthritis (PsA) in patients with psoriasis.

Methods

We identified an incidence cohort of psoriasis subjects age ≥18 years diagnosed between January 1, 1970 and December 31, 1999 in a population‐based setting. Psoriasis diagnoses were validated by confirmatory diagnosis in the medical record. Incident and clinically recognized PsA subjects were classified according to the Classification of Psoriatic Arthritis (CASPAR) criteria. Cox proportional hazards models were used to identify predictors of PsA within the psoriasis cohort.

Results

The psoriasis incidence cohort comprised 1,633 subjects. Of these, 40 were diagnosed with PsA concurrently with psoriasis and were excluded from analysis. The remaining 1,593 psoriasis subjects had a mean age of 43 years and 50% were men. Over 20,936 person‐years of followup, 57 subjects were clinically recognized with new‐onset PsA, with a cumulative incidence of 1.7% (95% confidence interval [95% CI] 1.0–2.3%), 3.1% (95% CI 2.2–4.1%), and 5.1% (95% CI 3.7–6.6%) at 5, 10, and 20 years following psoriasis incidence, respectively. Psoriasis features associated with higher risk of PsA were scalp lesions (hazard ratio [HR] 3.89, 95% CI 2.18–6.94), nail dystrophy (HR 2.93, 95% CI 1.68–5.12), and intergluteal/perianal lesions (HR 2.35, 95% CI 1.32–4.19). Calendar year was not associated with risk of PsA (P = 0.15), indicating that the likelihood of PsA in psoriasis subjects did not change over time.

Conclusion

In this population‐based study, <10% of patients with psoriasis developed clinically recognized PsA during a 30‐year period. Psoriasis features associated with a higher likelihood of PsA were nail dystrophy, scalp lesions, and intergluteal/perianal psoriasis.
Economic burden of knee and hip osteoarthritis in spain
Authors: Loza Estibaliz , Lopez‐Gomez Juan Miguel , Abasolo Lydia , Maese Jesús , Carmona Loreto , Batlle‐Gualda Enrique ,   Artrocad Study Group
Published: January 2009

Objective

To estimate the direct and indirect osteoarthritis (OA)–attributable costs and predictors of costs of knee and hip OA in Spain.

Methods

This study included consecutive patients age ≥50 years with symptomatic and radiologic knee and/or hip OA who were seen at primary care centers in all provinces of Spain. Information on demographics, health status (Short Form 12 Health Survey), comorbidities (Charlson Index), clinical (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]) and radiologic OA severity (Kellgren/Lawrence [K/L] scale), data related to OA health resources utilization (medical and nonmedical), and subjects' and caregivers' expenses and time lost in the previous 6 months were collected in 2 separate, structured, and detailed interviews. Costs in euros were assigned using market prices and official sources if available, and were annualized (to 2007). The predictors of costs were assessed in multivariate regression models. Costs were log‐transformed before being modeled.

Results

A total of 1,071 subjects were analyzed (74% women, mean ± SD age 71 ± 9 years). Average total annual costs were €1,502 per patient. Direct costs accounted for 86% of the total cost. We estimated a national cost of €4,738 million, representing 0.5% of the gross national product. Higher total costs were associated with comorbidity (Charlson Index odds ratio [OR] 1.27, 95% confidence interval [95% CI] 1.03–1.58), poorer health status (P < 0.050), worse WOMAC scores (OR 1.05, 95% CI 1.03–1.08), and grade 4 K/L scores (OR 1.76, 95% CI 1.15–2.69).

Conclusion

The economic burden of knee and hip OA is substantial. Costs increased with comorbidity, poorer health status, and clinical and radiologic OA severity.