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The effect of various oxygen passivation treatments on a 15 wt% MoP/SiO and a 15 wt% NiP/SiO catalyst is reported. Approximately 85 % of the MoP was re-oxidized when the MoP/SiO catalyst was passivated or simply exposed to air, whereas only about 40 % of the NiP was re-oxidized when the NiP/SiO catalyst was treated similarly. A second reduction of the catalysts after the passivation, followed by CO uptake measurements, showed an increase in CO uptake in the case of the MoP/SiO and a significant loss in CO uptake on the NiP/SiO when compared to the CO uptake measurements of the corresponding non-passivated samples. The oxidized species that resulted from the passivation of the NiP/SiO were much more easily reduced than those on the MoP/SiO. The loss in CO uptake observed in the case of the NiP/SiO is attributed to sintering and/or restructuring of the NiP during the second reduction step. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Squamate reptiles (snakes, lizards, amphisbaenians) rely heavily on chemosensory cues to identify, locate and choose between suitable prey items, but comparatively little research has focused on the chemical ecology of threatened squamate species. Such knowledge highlights ecologically important aspects of their survival. Due to gape limitations, squamates often demonstrate ontogenetic shifts in their diet where they consume larger prey as they grow older and their gape size increases. This shift enables squamates-especially snakes-to exploit new resources in their environments, usually mammalian prey. To test for ontogenetic variation in prey odor responses of a threatened snake species, the Northern pine snake ( Pituophis melanoleucus melanoleucus), we presented food-naïve neonates and food-experienced adults with potential prey and non-prey animal scents and quantified their behavioral responses. Our data indicate a strong response to rodent scents from both neonates and adults. Further, neonates showed more frequent investigative probing and retreating behaviors from scented swabs and a higher rate of tongue-flicking than adults. We also developed a new metric for measuring snake responses to prey odor, a tongue-flick reaction score (TFRS), that incorporates investigative behaviors that may be unique to constrictor-type snakes. The TFRS did not differ between age classes and was highest when rodent odors were tested. A canonical discriminant analysis confirmed the relationship between TFRS behavioral components and tested chemical signal reactions. Based on our data, P. melanoleucus may fall into a category of snakes that exhibit an ontogenetic telescope rather than a general ontogenetic shift in their prey odor responses. [ABSTRACT FROM AUTHOR]

Robust predictions of genetic variances for important traits would facilitate greater genetic gains in plant breeding. Previous attempts to predict the genetic variance ( σ G 2 ) of traits in bi-parental breeding populations were inconsistent and context specific. The weakness of methods that consider the phenotypic distance, genetic distance, and relationship-based distance of pairs of parents, which we collectively term historical methods, stems from the fact that they do not explicitly model the segregation of the underlying genetic effects for a trait within a population. To address this issue, we propose the use of three modern methods made possible by the commonplace use of genomewide molecular marker data and genomic selection in modern breeding programs. These modern methods utilize both phenotypic and genotypic records to, in varying degrees, explicitly model the segregation of informative genomewide markers to predict σ G 2 in bi-parental breeding populations. In this study, we evaluate the accuracy of historical and modern methods to predict σ G 2 using 40 field-tested bi-parental barley breeding populations evaluated during 2003–2010 for Fusarium head blight severity. In general, the modern methods predicted the field-based estimates of σ G 2 more accurately than the historical methods. Specifically, the modern method that most explicitly models the segregation of informative genomewide markers, called ‘PopVar,’ was the most accurate σ G 2 prediction method. [ABSTRACT FROM AUTHOR]

Correction to: I Nature Communications i https://doi.org/10.1038/s41467-019-13364-2, published online 29 November 2019. Since the publication of this work, Brittany M. Curtiss has changed their name from Brittany M. Smith. [Extracted from the article]

Genomic imprinting is an epigenetic process that restricts gene expression to either the maternally or paternally inherited allele. Many theories have been proposed to explain its evolutionary origin, but understanding has been limited by a paucity of data mapping the breadth and dynamics of imprinting within any organism. We generated an atlas of imprinting spanning 33 mouse and 45 human developmental stages and tissues. Nearly all imprinted genes were imprinted in early development and either retained their parent-of-origin expression in adults or lost it completely. Consistent with an evolutionary signature of parental conflict, imprinted genes were enriched for coexpressed pairs of maternally and paternally expressed genes, showed accelerated expression divergence between human and mouse, and were more highly expressed than their non-imprinted orthologs in other species. Our approach demonstrates a general framework for the discovery of imprinting in any species and sheds light on the causes and consequences of genomic imprinting in mammals. [ABSTRACT FROM AUTHOR]

Key message: We report malt quality QTLs relevant to breeding with greater precision than previous mapping studies. The distribution of favorable alleles suggests strategies for marker-assisted breeding and germplasm exchange. Abstract: This study leverages the breeding data of 1,862 barley breeding lines evaluated in 97 field trials for genome-wide association study of malting quality traits in barley. The mapping panel consisted of six-row and two-row advanced breeding lines from eight breeding populations established at six public breeding programs across the United States. A total of 4,976 grain samples were subjected to micro-malting analysis and mapping of nine quality traits was conducted with 3,072 SNP markers distributed throughout the genome. Association mapping was performed for individual breeding populations and for combined six-row and two-row populations. Only 16 % of the QTL we report here had been detected in prior bi-parental mapping studies. Comparison of the analyses of the combined two-row and six-row panels identified only two QTL regions that were common to both. In total, 108 and 107 significant marker-trait associations were identified in all six-row and all two-row breeding programs, respectively. A total of 102 and 65 marker-trait associations were specific to individual six-row and two-row breeding programs, respectively indicating that most marker-trait associations were breeding population specific. Combining datasets from different breeding program resulted in both the loss of some QTL that were apparent in the analyses of individual programs and the discovery of new QTL not identified in individual programs. This suggests that simply increasing sample size by pooling samples with different breeding history does not necessarily increase the power to detect associations. The genetic architecture of malting quality and the distribution of favorable alleles suggest strategies for marker-assisted selection and germplasm exchange. [ABSTRACT FROM AUTHOR]

A renewed interest in breeding barley specifically for food end-uses is being driven by increased consumer interest in healthier foods. We conducted association mapping on physicochemical properties of barley that play a role in food quality and processing including grain hardness, polyphenol oxidase activity, total phenolics, amylose content, and β-glucan. We used 3,069 elite two-row and six-row spring barley breeding lines from eight US breeding programs and 2,041 SNP markers for association mapping. Marker-trait associations were identified using a mixed model that incorporated population structure and kinship. We detected two previously identified QTL for grain hardness on chromosome 2H in the telomeric region of 5H along with two novel regions on 4H and 6H. For amylose content, we detected marker-trait associations on 7H from 0.63 to 30 cM. We detected four regions on chromosomes 1H, 2H, 3H, and 4H associated with polyphenol oxidase activity. The chromosome 2H region co-localized with the two previously mapped polyphenol oxidase genes PPO1 and PPO2, and the regions on chromosomes 1H, 3H, and 4H QTL were novel. For total phenolics, we identified three significant regions on 3H, 4H, and 5H. Two regions on 2H and 7H were associated with β-glucan. Both previously identified and novel QTL are segregating in elite US breeding germplasm. Only three of the 24 SNPs that were associated with traits using either the two-row or six-row mapping panel were identified in both panels. Nine SNPs were detected in the individual two-row or six-row panels that were not detected in the analysis using the complete panel and accounting for population structure. The distribution of favorable alleles at these loci that underpin food quality across the breeding programs suggests several strategies to use markers to improve barley for food uses. [ABSTRACT FROM AUTHOR]

The preparation of unsupported NiMoP catalysts in the presence of citric acid (CA) is reported. Phase pure NiMoP with a surface area ~60 m/g was synthesized in the presence of CA at low reduction temperature (550 °C), with a Ni/Mo/P molar ratio of 1/1/1 and a 1.5 CA/Me ratio (Me = Ni + Mo). Depending on the synthesis conditions, small amounts of MoP and NiMoP were also present in the catalysts. The catalyst precursors appeared similar to those identified for MoP and NiP catalysts, also synthesized in the presence of CA. For the phase pure NiMoP catalysts, the TOFs for the HDS of 4,6-dimethyldibenzothiophene were almost identical, despite large differences in NiMoP surface area and crystallite size. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Although sleep-disordered breathing has been extensively studied in patients with left-ventricular dysfunction, little is known of its prevalence in adults with congenital heart disease. Patients with d-looped transposition of the great arteries (d-TGA) who have undergone atrial switch procedures often develop progressive heart failure. The objective of this study was to determine the prevalence of patients at risk for sleep-disordered breathing in adults with d-TGA and atrial switch procedures compared with a control population. Thirty-two patients with d-TGA (66 % males, median age 31) were compared with 32 healthy controls. Baseline demographics and clinical characteristics were documented. The snoring, tiredness during daytime, observed apnea, and high blood pressure (STOP) questionnaire was used to identify subjects at risk for obstructive sleep apnea (OSA). There was no difference in baseline demographics between subjects and controls. For the STOP questionnaire, 14 subjects with d-TGA had scores predictive of OSA compared with three in the control group (44 vs. 9 %, p = 0.0038). There was no difference in functional status between d-TGA patients with or without OSA. There is a greater prevalence of risk for sleep disordered breathing in adults with d-TGA compared with controls. Further prospective investigation with sleep studies will be valuable to confirm these findings. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) and its associated mycotoxin, deoxynivalenol (DON), are the major biotic factors limiting cereal production in many parts of the world. A recent association mapping (AM) study of US six-row spring barley identified several modest effect quantitative trait loci (QTL) for DON and FHB. To date, few studies have attempted to verify the results of association analyses, particularly for complex traits such as DON and FHB resistance in barley. While AM methods use measures to control for the effects of population structure and multiple testing, false positive associations may still occur. A previous AM study used elite breeding germplasm to identify QTL for FHB and DON. To verify the results of that study, we evaluated the effects of the nine DON QTL using near-isogenic lines (NILs). We created families of contrasting homozygous haplotypes from lines in the original AM populations that were heterozygous for the DON QTL. Seventeen NIL families were evaluated for FHB and DON in three field experiments. Significant differences between contrasting NIL haplotypes were detected for three QTL across environments and/or genetic backgrounds, thereby confirming QTL from the original AM study. Several explanations for those QTL that were not confirmed are discussed, including the effect of genetic background and incomplete sampling of relevant haplotypes. [ABSTRACT FROM AUTHOR]

The effect of annealing temperature on the structure of unsupported Co-promoted MoS nanosheets, prepared by mechanical activation of MoO, S and Co(NO)·6HO followed by annealing in an Ar atmosphere, is reported. An increase in annealing temperature reduced the catalyst surface area but increased the MoS stack height. Annealing temperatures above 600 °C also produced segregated CoS phases. The dibenzothiophene hydrodesulphurization activity and the direct desulfurization (DDS) to hydrogenation product ratio of the Co-MoS catalysts was significantly higher than for MoS. Moreover, the DDS product selectivity of the Co-MoS catalysts was enhanced with increased annealing temperature up to 600 °C. Above 600 °C, the loss in activity and selectivity was due to segregation of CoS species and significant sintering of the MoS crystallites. Similar effects of high temperature sintering on the activity of MoS were also observed. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

We developed a targeted RNA sequencing method that couples microfluidics-based multiplex PCR and deep sequencing (mmPCR-seq) to uniformly and simultaneously amplify up to 960 loci in 48 samples independently of their gene expression levels and to accurately and cost-effectively measure allelic ratios even for low-quantity or low-quality RNA samples. We applied mmPCR-seq to RNA editing and allele-specific expression studies. mmPCR-seq complements RNA-seq for studying allelic variations in the transcriptome. [ABSTRACT FROM AUTHOR]

There is a growing interest in empirically exploring the biological underpinnings of political attitudes and behavior. Heritability studies are a primary vehicle for conducting such investigations and data sets rich in political phenotypes are becoming broadly accessible. A bottleneck exists, however, in exploiting these opportunities because they involve a statistical re-tooling for political scientists and require a conceptual shift that has substantial implications for the field's traditional theoretical models. Methodologically, most twin studies rely on structural equation models unfamiliar to political scientists. We show this methodological bottleneck is easily navigable; it is the lesser discussed shift in theoretical assumptions poses the larger problem to integrating biological elements into the study of political attitudes and behavior. To address these issues we provide a detailed introduction to a regression-based method for analyzing genetic influence on political attitudes and behaviors that will be methodologically intuitive to political scientists with even minimum quantitative training. In doing so, we provide a platform for bridging important conceptual divides between political science and behavioral genetics. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is a threat to barley ( Hordeum vulgare L.) production in many parts of the world. A number of barley accessions with partial resistance have been reported and used in mapping experiments to identify quantitative trait loci (QTL) associated with FHB resistance. Here, we present a set of barley germplasm that exhibits FHB resistance identified through screening a global collection of 23,255 wild ( Hordeum vulgare ssp. spontaneum) and cultivated ( Hordeum vulgare ssp. vulgare) accessions. Seventy-eight accessions were classified as resistant or moderately resistant. The collection of FHB resistant accessions consists of 5, 27, 46 of winter, wild and spring barley, respectively. The population structure and genetic relationships of the germplasm were investigated with 1,727 Diversity Array Technology (DArT) markers. Multiple clustering analyses suggest the presence of four subpopulations. Within cultivated barley, substructure is largely centered on spike morphology and growth habit. Analysis of molecular variance indicated highly significant genetic variance among clusters and within clusters, suggesting that the FHB resistant sources have broad genetic diversity. The haplotype diversity was characterized with DArT markers associated with the four FHB QTLs on chromosome 2H bin8, 10 and 13 and 6H bin7. In general, the wild barley accessions had distinct haplotypes from those of cultivated barley. The haplotype of the resistant source Chevron was the most prevalent in all four QTL regions, followed by those of the resistant sources Fredrickson and CIho4196. These resistant QTL haplotypes were rare in the susceptible cultivars and accessions grown in the upper Midwest USA. Some two- and six-rowed accessions were identified with high FHB resistance, but contained distinct haplotypes at FHB QTLs from known resistance sources. These germplasm warrant further genetic studies and possible incorporation into barley breeding programs. [ABSTRACT FROM AUTHOR]

Political involvement varies markedly across people. Traditional explanations for this variation tend to rely on demographic variables and self-reported, overtly political concepts. In this article, we expand the range of possible explanatory variables by hypothesizing that a correlation exists between political involvement and physiological predispositions. We measure physiology by computing the degree to which electrodermal activity changes on average when a participant sequentially views a full range of differentially valenced stimuli. Our findings indicate that individuals with higher electrodermal responsiveness are also more likely to participate actively in politics. This relationship holds even after the effects of traditional demographic variables are taken into account, suggesting that physiological responsiveness independently contributes to a fuller understanding of the underlying sources of variation in political involvement. [ABSTRACT FROM AUTHOR]

The genetic basis of agronomic traits determining adaptation to specific production conditions is a key factor for the improvement of crops, including malting barley ( Hordeum vulgare L.). The aim of this study was to determine the genome-wide genetic components associated with agronomic phenotypes of local and global significance in a population of 76 barley genotypes that have been introduced into Uruguay in different chronological periods. The phenotypic database was obtained from five field experiments, planted in 2 years and in two locations, where a total of 13 agronomic traits were determined. The population was genotyped with 1,033 single nucleotide polymorphisms. We found a total of 41 quantitative trait loci (QTL) in a combined analysis using all datasets and 79 QTL if we considered all the trait/experiment combinations analyzed. The highest concentration of QTL was detected on chromosomes 2H and 4H. Most QTL were detected for grain plumpness and weight. Two linkage disequilibrium (LD) blocks associated with a large number of traits were detected on 2HS. The largest LD block was composed of three haplotypes, possibly derived from three ancestors of different geographical origin. We also detected three genomic regions in different chromosomes (2H, 5H and 7H) in LD between them, associated with agronomic traits. This study provides a contribution to the understanding of the genetics of barley adaptation in the southern cone of South America. Our results showed that elite varieties have favorable alleles at different QTL, indicating that gains can be made through plant breeding. [ABSTRACT FROM AUTHOR]

Fall-sown barley will be increasingly important in the era of climate change due to higher yield potential and efficient use of water resources. Resistance/tolerance to abiotic stresses will be critical, and foremost among the abiotic stresses is low temperature. Simultaneous gene discovery and breeding will accelerate the development of agronomically relevant fall-sown barley germplasm with resistance to low temperature. We developed two doubled haploid mapping populations using two lines from the University of Nebraska (NE) and one line from Oregon State University (OR): NB3437f/OR71 (facultative × facultative) and NB713/OR71 (winter × facultative). Both were genotyped with a custom 384 oligonucleotide pool assay (OPA). QTL analyses were performed for low temperature tolerance (LTT) and vernalization sensitivity (VS). The role of VRN- H2 in VS was confirmed and a novel alternative winter allele at VRN- H3 was discovered in the Nebraska germplasm. FR- H2 was identified as a probable determinant of LTT and a new QTL, FR- H3, was discovered on chromosome 1H that accounted for up to 48 % of the phenotypic variation in field survival at St. Paul, MN, USA. The discovery of FR- H3 is a significant advancement in barley LTT genetics and will assist in developing the next generation of fall-sown varieties. [ABSTRACT FROM AUTHOR]

Trophic interactions can strongly influence the structure and function of terrestrial and aquatic communities through top-down and bottom-up processes. Species with life stages in both terrestrial and aquatic systems may be particularly likely to link the effects of trophic interactions across ecosystem boundaries. Using experimental wetlands planted with purple loosestrife ( Lythrum salicaria), we tested the degree to which the bottom-up effects of floral density of this invasive plant could trigger a chain of interactions, changing the behavior of terrestrial flying insect prey and predators and ultimately cascading through top-down interactions to alter lower trophic levels in the aquatic community. The results of our experiment support the linkage of terrestrial and aquatic food webs through this hypothesized pathway, with high loosestrife floral density treatments attracting high levels of visiting insect pollinators and predatory adult dragonflies. High floral densities were also associated with increased adult dragonfly oviposition and subsequently high larval dragonfly abundance in the aquatic community. Finally, high-flower treatments were coupled with changes in zooplankton species richness and shifts in the composition of zooplankton communities. Through changes in animal behavior and trophic interactions in terrestrial and aquatic systems, this work illustrates the broad and potentially cryptic effects of invasive species, and provides additional compelling motivation for ecologists to conduct investigations that cross traditional ecosystem boundaries. [ABSTRACT FROM AUTHOR]

Unsupported, high surface area MoP and NiP catalysts were synthesized by adding citric acid (CA) to solutions of ammonium heptamolybdate and diammonium hydrogen phosphate or nickel nitrate and diammonium hydrogen phosphate, respectively, followed by drying (397 K), calcination (773 K), and reduction in H (923 K). The addition of CA increased the surface area, decreased the particle size, and increased the CO uptake of the MoP and NiP catalysts. At 623 K and 4.4 MPa, the NiP was 2.3 times more active than the MoP on a mass basis and 6 times more active on a site basis for the hydrodeoxygenation of 4-methylphenol. However, the NiP catalysts deactivated due to non-selective carbon deposition on the catalyst surface. Oxidation was excluded as a potential cause of deactivation over the NiP catalysts. The rate of deactivation was well described by an exponential decay law. Deactivation was eliminated by operation at higher H pressures (5.3 and 6.1 MPa) but the hydrogenation selectivity of the NiP increased at these conditions. No deactivation was observed over the MoP catalysts at the conditions of the present study. [ABSTRACT FROM AUTHOR]

Over the past two decades many quantitative trait loci (QTL) have been detected; however, very few have been incorporated into breeding programs. The recent development of genome-wide association studies (GWAS) in plants provides the opportunity to detect QTL in germplasm collections such as unstructured populations from breeding programs. The overall goal of the barley Coordinated Agricultural Project was to conduct GWAS with the intent to couple QTL detection and breeding. The basic idea is that breeding programs generate a vast amount of phenotypic data and combined with cheap genotyping it should be possible to use GWAS to detect QTL that would be immediately accessible and used by breeding programs. There are several constraints to using breeding program-derived phenotype data for conducting GWAS namely: limited population size and unbalanced data sets. We chose the highly heritable trait heading date to study these two variables. We examined 766 spring barley breeding lines (panel #1) grown in balanced trials and a subset of 384 spring barley breeding lines (panel #2) grown in balanced and unbalanced trials. In panel #1, we detected three major QTL for heading date that have been detected in previous bi-parental mapping studies. Simulation studies showed that population sizes greater than 384 individuals are required to consistently detect QTL. We also showed that unbalanced data sets from panel #2 can be used to detect the three major QTL. However, unbalanced data sets resulted in an increase in the false-positive rate. Interestingly, one-step analysis performed better than two-step analysis in reducing the false-positive rate. The results of this work show that it is possible to use phenotypic data from breeding programs to detect QTL, but that careful consideration of population size and experimental design are required. [ABSTRACT FROM AUTHOR]

Online travel agencies (OTAs) play a more and more important role in the tourism and hospitality industry by contributing to a large volume of transactions and revenue. Many studies have evaluated tourism websites through different research methods. Website usability in general has improved dramatically but problems remain. Very few studies focus on the user behavior and usability of a single OTA website. This research uses a mixed-methods approach, including eye tracking methodology to study information search strategy and the usability problems of a major OTA site with a predefined information search task. The results show that users' information search is mostly utilitarian in nature; the complex interface and advertising messages either confuse or were ignored by most users. The study calls for a simpler and more intuitive interface. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB), primarily caused by Fusarium graminearum, reduces grain yield and quality in barley. Resistance to FHB is partial and quantitatively inherited. Previously, major FHB resistant QTL were detected on barley chromosome 2H Bin 8 and 2H Bin 10, and another QTL for reduced deoxynivalenol (DON) accumulation was identified on chromosome 3H Bin 6. To develop an understanding of the molecular responses controlled by these loci, we examined DON and fungal biomass levels and the transcriptome differences in near-isogenic line (NIL) pairs carrying contrasting resistant and susceptible alleles at these QTL during F. graminearum infection. No overlap was found among the differentially accumulated transcripts of the three NIL pairs, indicating that the response to infection controlled by the resistance alleles at each QTL may be distinct. Transcripts showing differential accumulation between resistant and susceptible NILs were compared to results from previous wheat/barley- F. graminearum studies and integrated into a wheat/barley- F. graminearum interaction model. [ABSTRACT FROM AUTHOR]

Perennial ryegrass is a globally cultivated obligate outbreeding diploid species (2 n = 2 x = 14) which is subjected to periods of waterlogging stress due to flood irrigation during winter and the lead-up to summer. Reduction of oxygen supply to root systems due to waterlogging produces consequent deleterious effects on plant performance. Framework genetic maps for a large-scale genetic mapping family [ F(NA × AU)] were constructed containing 91 simple sequence repeat and 24 single nucleotide polymorphism genetic markers. Genetic trait dissection using both control and waterlogging treatments was performed in the glasshouse, a total of 143 maximally recombinant genotypes being selected from the overall sib-ship and replicated threefold in the trial. Analysis was performed for nine quantitative morphological traits measured 8 weeks after stress treatments were applied. A total of 37 quantitative trait loci (QTLs) were identified; 19 on the NA parental genetic map, and 18 on the AU parental genetic map. Regions of particular interest were identified on linkage groups (LGs) 4 and 3 of the respective maps, which have been targeted for further analysis by selection of critical recombinants. This first study of genetic control of waterlogging tolerance in ryegrasses has important implications for breeding improvement of abiotic stress adaptation. [ABSTRACT FROM AUTHOR]

Gaze cues lead to reflexive shifts of attention even when those gaze cues do not predict target location. Although this general effect has been repeatedly demonstrated, not all individuals orient to gaze in an identical manner. For example, the magnitude of gaze-cuing effects have been reduced or eliminated in populations such as those scoring high on the Autism-Spectrum Quotient and in males relative to females (since males exhibit more autism-like traits). In the present study, we examined whether gaze cue effects would be moderated by political temperament, given that those on the political right tend to be more supportive of individualism-and less likely to be influenced by others-than those on the left. We found standard gaze-cuing effects across all subjects but systematic differences in these effects by political temperament. Liberals exhibited a very large gaze-cuing effect, whereas conservatives showed no such effect at various stimulus onset asynchronies. [ABSTRACT FROM AUTHOR]

Spot blotch, caused by Cochliobolus sativus, is an important foliar disease of barley. The disease has been controlled for over 40 years through the deployment of cultivars with durable resistance derived from the line NDB112. Pathotypes of C. sativus with virulence for the NDB112 resistance have been detected in Canada; thus, many commercial cultivars are vulnerable to spot blotch epidemics. To increase the diversity of spot blotch resistance in cultivated barley, we evaluated 318 diverse wild barley accessions comprising the Wild Barley Diversity Collection (WBDC) for reaction to C. sativus at the seedling stage and utilized an association mapping (AM) approach to identify and map resistance loci. A high frequency of resistance was found in the WBDC as 95% (302/318) of the accessions exhibited low infection responses. The WBDC was genotyped with 558 Diversity Array Technology (DArT®) and 2,878 single nucleotide polymorphism (SNP) markers and subjected to structure analysis before running the AM procedure. Thirteen QTL for spot blotch resistance were identified with DArT and SNP markers. These QTL were found on chromosomes 1H, 2H, 3H, 5H, and 7H and explained from 2.3 to 3.9% of the phenotypic variance. Nearly half of the identified QTL mapped to chromosome bins where spot blotch resistance loci were previously reported, offering some validation for the AM approach. The other QTL mapped to unique genomic regions and may represent new spot blotch resistance loci. This study demonstrates that AM is an effective technique for identifying and mapping QTL for disease resistance in a wild crop progenitor. [ABSTRACT FROM AUTHOR]

The production of isobutanol in microorganisms has recently been achieved by harnessing the highly active 2-keto acid pathways. Since these 2-keto acids are precursors of amino acids, we aimed to construct an isobutanol production platform in Corynebacterium glutamicum, a well-known amino-acid-producing microorganism. Analysis of this host’s sensitivity to isobutanol toxicity revealed that C. glutamicum shows an increased tolerance to isobutanol relative to Escherichia coli. Overexpression of alsS of Bacillus subtilis, ilvC and ilvD of C. glutamicum, kivd of Lactococcus lactis, and a native alcohol dehydrogenase, adhA, led to the production of 2.6 g/L isobutanol and 0.4 g/L 3-methyl-1-butanol in 48 h. In addition, other higher chain alcohols such as 1-propanol, 2-methyl-1-butanol, 1-butanol, and 2-phenylethanol were also detected as byproducts. Using longer-term batch cultures, isobutanol titers reached 4.0 g/L after 96 h with wild-type C. glutamicum as a host. Upon the inactivation of several genes to direct more carbon through the isobutanol pathway, we increased production by ∼25% to 4.9 g/L isobutanol in a ∆ pyc∆ ldh background. These results show promise in engineering C. glutamicum for higher chain alcohol production using the 2-keto acid pathways. [ABSTRACT FROM AUTHOR]

Allotetraploid (2 n = 4 x = 32) white clover ( Trifolium repens L.) is the most commonly cultivated legume component of temperate pastures, sown in swards with a companion grass species. Genetic control of growth performance of white clover on saline land is highly important for dairy industries, due to increasing soil salinity problems. The objective of this study was to identify quantitative trait loci (QTLs) for salinity tolerance in terms of vegetative growth under stress. Two parental genetic maps consisting of 213 and 159 marker loci and spanning 1,973.0 and 1,837.6 cM, respectively, were constructed using simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers from a two-way pseudo-test cross F1 population derived from pair-crossing of the Haifa2 and LCL2 genotypes. A total of 8 unique genomic regions on 8 linkage groups (LGs) of the Haifa2 parental map and 6 unique regions on 5 LGs in the LCL2 parental map were associated with plant growth under salt stress and relative growth under stress, as compared to control conditions. The results of this study indicate that salt tolerance in white clover is controlled by multiple QTLs, some at common locations, but each of limited magnitude. Location of these QTLs provides the genetic basis and potential for pyramiding of salt tolerance genes in breeding improvement. [ABSTRACT FROM AUTHOR]

In previous studies, we demonstrated that elongation of side chains of several sensitizers endowed them with higher affinity for artificial and natural membranes and caused their deeper localization in membranes. In the present study, we employed eight hematoporphyrin and protoporphyrin analogs and four groups containing three chlorin analogs each, all synthesized with variable numbers of methylenes in their alkyl carboxylic chains. We show that these tetrapyrroles’ affinity for bovine serum albumin (BSA) and their localization in the binding site are also modulated by chain lengths. The binding constants of the hematoporphyrins and protoporphyrins to BSA increased as the number of methylenes was increased. The binding of the chlorins depended on the substitution at the meso position opposite to the chains. The quenching of the sensitizers’ florescence by external iodide ions decreased as the side chains became longer, indicating to deeper insertion of the molecules into the BSA binding pocket. To corroborate this conclusion, we studied the efficiency of photodamage caused to tryptophan in BSA upon illumination of the bound sensitizers. The efficiency was found to depend on the side-chain lengths of the photosensitizer. We conclude that the protein site that hosts these sensitizers accommodates different analogs at positions that differ slightly from each other. These differences are manifested in the ease of access of iodide from the external aqueous phase, and in the proximity of the photosensitizers to the tryptophan. In the course of this study, we developed the kinetic equations that have to be employed when the sensitizer itself is being destroyed. [ABSTRACT FROM AUTHOR]

Glycogen synthase kinase 3 (GSK3) is a multifunctional serine/threonine kinase that participates in numerous signalling pathways involved in diverse physiological processes. Several of these pathways are implicated in disease pathogenesis, which has prompted efforts to develop GSK3-specific inhibitors for therapeutic applications. However, before now, there has been no strong rationale for targeting GSK3 in malignancies. Here we report pharmacological, physiological and genetic studies that demonstrate an oncogenic requirement for GSK3 in the maintenance of a specific subtype of poor prognosis human leukaemia, genetically defined by mutations of the MLL proto-oncogene. In contrast to its previously characterized roles in suppression of neoplasia-associated signalling pathways, GSK3 paradoxically supports MLL leukaemia cell proliferation and transformation by a mechanism that ultimately involves destabilization of the cyclin-dependent kinase inhibitor p27Kip1. Inhibition of GSK3 in a preclinical murine model of MLL leukaemia provides promising evidence of efficacy and earmarks GSK3 as a candidate cancer drug target. [ABSTRACT FROM AUTHOR]

Predation, competition, and their interaction are known to be important factors that influence the structure of ecological communities. In particular, in those cases where a competitive hierarchy exists among prey species, the presence of certain keystone predators can result in enhanced diversity in the prey community. However, little is known regarding the influence of keystone predator presence on invaded prey communities. Given the widespread occurrence of invasive species and substantial concern regarding their ecological impacts, studies on this topic are needed. In this study I used naturalistic replications of an experimental tadpole assemblage to assess the influence of predatory eastern newts, Notophthalmus viridescens, on the outcome of interspecific competition among native and nonindigenous tadpoles. When newts were absent, the presence of the tadpoles of one invasive species, the Cuban treefrog, Osteopilus septentrionalis, resulted in decreased survival and growth rate of the dominant native species, Bufo terrestris, and dominance of the tadpole assemblage by O. septentrionalis. However, the presence of one adult newt generally reduced or eliminated the negative impacts of O. septentrionalis tadpoles, resulting in comparable survival and performance of native species in invaded and noninvaded treatments. Differential mortality among the tadpole species suggests that newts preyed selectively on O. septentrionalis tadpoles, supporting the hypothesis that newts acted as keystone predators in the invaded assemblage. The presence of nonindigenous larval cane toads, Bufo marinus, did not significantly affect native species, and this species was not negatively affected by the presence of newts. Collectively, these results suggest that eastern newts significantly modified the competitive hierarchy of the invaded tadpole assemblage and reduced the impacts of a competitively superior invasive species. If general, these results suggest that the presence of certain species may be an essential factor regulating the ecological impacts of biological invasions. [ABSTRACT FROM AUTHOR]

The activity of exfoliated MoS2 in the hydrodesulfurization (HDS) of dibenzothiophene, the hydrodenitrogenation (HDN) of carbazole and the hydrogenation of naphthalene has been determined. The catalytic activity was compared to MoS2 prepared by the decomposition of molybdenum naphthenate (MoNaph). Exfoliated MoS2 was found to give better overall HDS activity compared to MoNaph derived MoS2 catalyst, whereas MoNaph derived MoS2 was found to give higher hydrogenation and HDN activity. These results are discussed in terms of the morphology of the two catalysts. The relative activity of the two catalysts in the hydrotreating reactions is shown to be different to that obtained during Cold Lake bitumen hydrocracking. [ABSTRACT FROM AUTHOR]