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Hybrid 2D Raman-terahertz (THz) spectroscopy is used to measure the interactions between two solvents paired in the binary CHBr3-MeOH mixture in the frequency range of 1-7 THz. Changes in the cross peak signature are monitored, originating from the coupling of an intramolecular bending mode of CHBr3 to the collective intermolecular degrees of freedom of the mixture. The appearance of a new cross peak in the 2D spectrum measured for solvent mixture with MeOH molar fraction of 0.3 indicates a coupling to a new set of low-frequency modes formed due to the hydrogen bond interactions between the two solvents. This interpretation is supported by the measurement of the CHBr3-CS2 binary solvent mixture as well as by 1D absorption measurements of neat MeOH.
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BACKGROUND: This study presents a count of publications and citations for all articles published by university Departments of Anaesthesiology in Germany, Austria and Switzerland between 2011 and 2015. The results were compared with former analyses of these countries from 2001-2010 as well as similar international studies. METHODS: We performed a PubMed search based on PERL-scripts for all publications originating from university Departments of Anaesthesiology in Germany, Austria and Switzerland between 2011 and 2015. According to their author's affiliation, articles were assigned to their affiliated university department. Publications were considered an original article if the category of publication was classified as original research in PubMed. Predatory journals were omitted by using PubMed-listed journals only. Data of citations was retrieved from Thomson Reuter's ISI Web of Knowledge. The following indicators were reported: the number of publications and original articles (counting each author and first authors only) and the share of original articles out of all publications. With regard to citations, we reported the overall number, the percentage of publications, which were cited at least once and the median of citations per publication and per original article as well as the calculated h-index. RESULTS: The 47 university Departments of Anaesthesiology published 4.697 articles between 2011 and 2015, which make up 89% of all anaesthesiology research originating from Germany, Austria and Switzerland (overall 5.284 publications). Of these, 1.037 (22%) were classified as original articles. Considering only articles with first authors, equalizing a change of PubMed's affiliation field policy in 2012 to compare the numbers with previous periods, 3.709 publications and 821 original articles were published. 90% of all publications and 96% of original articles, respectively, were cited at least once. Publications were cited six times, while original articles were cited nine times. The university department of Anaesthesiology in Zurich published most (nâ¯= 245), while most original articles were published in Vienna (nâ¯= 77). The highest share of original articles was achieved by Vienna (37%). Publications from Berlin - Benjamin Franklin and Jena (11 citations per publication) and original articles from Essen (23,5 citations per original article) achieved the highest citation rates. DISCUSSION: In contrast to the worldwide increasing trend, the number of publications of the university Departments of Anaesthesiology in Germany, Austria and Switzerland stagnated. The share of original articles out of all publications continues to decline in comparison to 2001-2010 (-6%). Despite this, original articles were cited more frequently and thus had a higher value for the scientific community. The reasons of the decrease in the number of original articles remain unclear and require further investigation to reverse this negative trend. CONCLUSION: Strategies to foster academic work in anaesthesiology in Germany, Austria and Switzerland are required.
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Anestesiología , Hospitales Universitarios , Edición/estadística & datos numéricos , Austria , Alemania , Humanos , SuizaRESUMEN
BACKGROUND: This study assessed the contribution made to research by Scandinavian university Departments of Anaesthesiology and their distribution among those departments. METHODS: We committed a PubMed search for all publications originating from Scandinavian university Departments of Anaesthesiology between 2001 and 2015. Articles were assigned to their author's affiliated university department and to 3 time periods 2001-2005, 2006-2010 and 2011-2015. The number of publications, original articles and citations were analysed. RESULTS: The 23 Scandinavian university Departments of Anaesthesiology published 5190 articles between 2001 and 2015, which make up 91.5% from all anaesthesiology research originating from Scandinavia. Of these 1760 (33.9%) were classified as original articles. The number of publications increased in the observed periods (from 1305 in 2001-2005 to 2452 in 2010-2015), but the share of original articles decreased (from 40% to 31%). Finnish university Departments of Anaesthesiology had the largest share of original articles. The university department of Copenhagen was the most productive Department of Anaesthesiology in terms of number of publications (n = 1187) and citation rate of original articles (median 24 citations per original article). Publications from Bergen scored the highest impact (median 19 citations per publication). CONCLUSIONS: The number of publications from Scandinavian university Departments of Anaesthesiology increased between 2001 and 2015, but the share of original articles decreased. Copenhagen was the most productive university Department of Anaesthesiology based on the number of publications and citations of original articles. Finnish university Departments of Anaesthesiology led in the share of original articles out of all publications.
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Servicio de Anestesia en Hospital/estadística & datos numéricos , Anestesiología/estadística & datos numéricos , Hospitales Universitarios/estadística & datos numéricos , Edición/estadística & datos numéricos , Bibliometría , Eficiencia , Investigación , Países Escandinavos y NórdicosRESUMEN
The aim of this study was to analyse publication trends from the anaesthetic literature of the G-20 countries. We performed a literature search in Medline to identify articles related to anaesthetic departments published between 2001 and 2015, by specific G-20 countries according to the affiliation field of the authors, and to three time periods 2001-2005, 2006-2010 and 2011-2015. The number of articles, number of original articles (vs. reviews, editorials or correspondence), articles per million inhabitants, and citations per article were analysed. In total, 96,920 articles were published between 2001 and 2015 in 74 anaesthetic and in 4117 non-anaesthetic journals, with an increase of +104% absolute (i.e. from 23,028 in 2001-05 to 46,887 articles ìn 2010-15) and +85% as articles per million inhabitants. Similarly, the number of original articles increased by 21%, but the anaesthetic specialty's share of original articles (as a proportion of total articles in biomedicine) decreased from 31% in 2001-2005 to 19% in 2011-2015 (-38%). The USA published most articles (2011-15 16,016; 31% of total), second came the EU as a whole and third Japan (from 2001 to 2005) or Germany (2006-2010) until 2011-2015 when China took over the third rank. In 2011-2015, Canada published most articles per million inhabitants (68.7 articles/million inhabitants). China and India exhibited the most publication growth 11- and 9-fold, respectively, and are now among the top five countries for the number of published articles.
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Anestesiología/tendencias , Bibliometría , Investigación Biomédica/tendencias , Publicaciones Periódicas como Asunto/tendencias , Edición/tendencias , Anestesiología/estadística & datos numéricos , Investigación Biomédica/estadística & datos numéricos , Humanos , Publicaciones Periódicas como Asunto/estadística & datos numéricos , Edición/estadística & datos numéricosRESUMEN
A new, general reaction scheme for photocatalytic hydrogen production is presented based on oxidative quenching of a homoleptic copper(I) bis-1,10-phenanthroline photosensitizer (PS) by 1-methyl-4-phenyl-pyridinium (MPP(+) ) as the electron relay and subsequent regeneration of the so formed copper(II) complex by a sacrificial electron donor. Electron transfer from the relay to various cobalt based water reduction catalysts and subsequent H2 production was shown to close the catalytic cycle. Transient absorption experiments unambiguously confirmed the proposed pathway, both the oxidative quenching and subsequent regeneration of oxidized PS. Photocatalytic test runs further confirmed the role of MPP(+) and up to 10â turnovers were achieved in the relay. The performance limiting factor of the system was shown to be the decomplexation of the copper PS. Quantum yields of the system were 0.03 for H2 production, but 0.6 for MPP(.) formation, clearly indicating that unproductive pathways still prevail.
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Cobre/química , Hidrógeno/química , Luz , Compuestos Organometálicos/química , Fenantrolinas/química , Procesos Fotoquímicos , Fármacos Fotosensibilizantes/química , 1-Metil-4-fenilpiridinio/química , Oxidación-ReducciónRESUMEN
AIM: This study assessed the publication performance of university departments of anesthesiology in Austria, Germany and Switzerland. The number of publications, original articles, impact factors and citations were evaluated. MATERIAL AND METHODS: A search was performed in PubMed to identify publications related to anesthesiology from 2001 to 2010. All articles from anesthesiology journals listed in the fields of anesthesia/pain therapy, critical care and emergency medicine by the "journal citation report 2013" in Thomson Reuters ISI web of knowledge were included. Articles from non-anaesthesiology journals, where the stem of the word anesthesia (anes*, anaes*, anäst*, anast*) appears in the affiliation field of PubMed, were included as well. The time periods 2001-2005 and 2006-2010 were compared. Articles were allocated to university departments in Austria, Germany and Switzerland via the affiliation field. RESULTS: A total of 45 university departments in Austria, Germany and Switzerland and 125,979 publications from 2,863 journals (65 anesthesiology journals, 2,798 non-anesthesiology journals) were analyzed. Of the publications 23 % could not be allocated to a given university department of anesthesiology. In the observation period the university department of anesthesiology in Berlin achieved most publications (n = 479) and impact points (1,384), whereas Vienna accumulated most original articles (n = 156). Austria had the most publications per million inhabitants in 2006-2010 (n=50) followed by Switzerland (n=49) and Germany (n=35). The number of publications during the observation period decreased in Germany (0.5 %), Austria (7 %) and Switzerland (8 %). Tables 2 and 4-8 of this article are available at Springer Link under Supplemental. CONCLUSIONS: The research performance varied among the university departments of anesthesiology in Germany, Austria and Switzerland whereby larger university departments, such as Berlin or Vienna published most. Publication output in Germany, Austria and Switzerland has decreased. Data processing in PubMed should be improved.
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Anestesiología/tendencias , Edición/tendencias , Universidades/tendencias , Anestesiología/estadística & datos numéricos , Austria , Alemania , Factor de Impacto de la Revista , PubMed/normas , PubMed/estadística & datos numéricos , Edición/estadística & datos numéricos , Suiza , Universidades/estadística & datos numéricosRESUMEN
Bermudagrass (Cynodon dactylon) is an important warm-season perennial turf and forage grass that is typically grown in warm, tropical and subtropical climates. Smutted inflorescences of bermudagrass were observed and collected in Benton County, Washington, United States, in October of 2012 in an unmanaged, naturalized area located near the banks of the Columbia River and adjacent to large expanses of managed turf containing bermudagrass. The climate in this area is favorable to bermudagrass due to the relatively mild winters and hot, dry summers that usually occur in this region. The infected plants occurred in patches alongside healthy plants and several disease foci were observed along a 100-m transect of non-contiguous bermudagrass. The disease was severe wherever it occurred. Diseased inflorescences were covered with black-brown teliospores, distorted, and frequently failed to fully emerge and develop. Teliospores (n = 80) were irregularly globose to subglobose, 5.3 to 7.0 × 4.5 to 6.2 µm (mean 6.4 × 5.9 µm) and 6.2 to 8.8 × 5.3 to 7.0 µm (mean 7.0 × 6.5 µm), with a smooth wall approximately 1 µm thick, and were consistent with previous descriptions of Ustilago cynodontis teliospores (1,3). Teliospores germinated within 24 h when plated on 0.2% malt agar at 16°C and produced 4-celled basidia in a 3+1 arrangement, also consistent with U. cynodontis (3). Basidia gave rise to lateral and terminal, ovoid to long ellipsoidal basidiospores. Basidiospores budded or germinated by hyphae from which lateral or terminal aerial sporidia developed as previously described (3,4). DNA was extracted from sporidia of three single-spored isolates grown in malt extract broth. Complete nucleotide sequences of the 5.8S ribosomal RNA coding region and partial sequences of the internal transcribed spacer (ITS) regions 1 and 2 were obtained from the three isolates using ITS1 and ITS4 primers. The corresponding regions of the three aligned sequences (GenBank Accession Nos. KC920742 to KC920744) were identical and exhibited 99 to 100% identity with U. cynodontis strains previously deposited in GenBank (HM143013, AY740168, AF038825, and AY345000). Representative specimens were deposited in the WSU Mycological Herbarium as WSP 72345 to WSP 72348. This is the first report of U. cynodontis causing smut on bermudagrass in Washington State and represents the northernmost record of this fungus in North America (2). The occurrence of U. cynodontis in Washington State suggests that the pathogen may exist in other hot and dry areas of northwestern North America where bermudagrass is found associated with turf in recreational, landscape, or natural settings. References: (1) S. D. Brook. Trans. R. Soc. N. Z. 84:643, 1957. (2) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Online. Retrieved from http://nt.ars-grin.gov/fungaldatabases , April 18, 2013. (3) C. T. Ingold. Trans. Br. Mycol. Soc. 83:251, 1984. (4) C. T. Ingold. Trans. Br. Mycol. Soc. 89:471, 1987.
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Potatoes are a major crop in the Columbia Basin of Oregon and Washington, representing an annual farm gate value of almost $750 million. Zebra chip disease (ZC), a new and economically important disease of potato, was first reported in Oregon and Washington in 2011 (1). The disease is caused by the bacterium 'Candidatus Liberibacter solanacearum' (Lso, also referred to as 'Ca. L. psyllaurous'), which is vectored by the potato psyllid (Bactericera cockerelli Sulc) (1,2). Identifying alternative hosts for Lso may facilitate management of ZC disease, which has increased potato production costs in the region. The perennial weed, bittersweet nightshade (Solanum dulcamara L.), is a year-round host of the potato psyllid (3) and is also a suspected host of Lso. However, little is known about the role of this weed in ZC epidemiology. Naturally occurring bittersweet nightshade plants (n = 21) were sampled at six different locations near Hermiston, Oregon, between May and October in 2012. These plants exhibited several symptoms associated with Lso, ranging from asymptomatic to slight purpling, chlorosis, or scorching of the foliage. However, S. dulcamara exhibits similar symptoms under a variety of environmental conditions (drought stress, etc.); therefore, it was difficult to identify potentially infected plants based solely on symptomology. Leaf and stem tissue (n = 21) was analyzed with high-fidelity PCR using species-specific primers for the 16S rDNA gene, CLipoF, and OI2c (2,4). Approximately 27.3% of the plants tested positive for Lso using these primers, including plants from the following locations on 16 April, 16 May, and 24 May, respectively: Hat Rock, OR (45°55.033' N, 119°10.495' W), Irrigon, OR (45°54.560' N, 119°24.857' W), and Stanfield, OR (45°46.971' N, 119°13.203' W). Three plants were selected for further PCR analysis with primers for the outer membrane protein gene, 1482f and 2086r (1). Amplicons obtained with both sets of PCR primers were directly sequenced. A BLAST analysis showed that the 16S rDNA gene sequence (993 to 1,000 bp) shared 99 to 100% identity with several Lso accessions, including JN848751.1 (from Washington) and JN848753.1 (from Oregon). Likewise, the outer membrane protein gene sequence (600 to 601 bp) shared 99 to 100% identity with 'Ca. L. solanacearum' accession KC768330.1 (from Honduras). All six sequences were deposited in GenBank (Accession Nos. KJ854199 to KJ854204). According to these findings, bittersweet nightshade may be an important annual source of Lso in the region, particularly since it serves as a host for the potato psyllid. Potato psyllids were also detected at two of the locations with infected S. dulcamara: Irrigon, OR, and Stanfield, OR. A subsample of the psyllids collected in 2012 were analyzed with PCR and Lso was detected in a sample from Stanfield, OR (5). Identifying perennial hosts of Lso promotes a better understanding of both ZC disease epidemiology and management. To our knowledge, this is the first report of Lso causing natural infections in S. dulcamara in the United States. References: (1) J. M. Crosslin et al. Plant Dis. 96:452, 2012. (2) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996. (3) A. F. Murphy et al. Am. J. Pot. Res. 90:294, 2013. (4) G. A. Secor et al. Plant Dis. 93:574, 2009. (5) K. D. Swisher et al. Am. J. Pot. Res. 90:570, 2013.
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In August of 2011, potato (Solanum tuberosum) tubers grown in the lower Columbia Basin of southern Washington State and northern Oregon were observed with internal discolorations suggestive of zebra chip disease (ZC). Symptoms included brown spots, streaks, and stripes in and near the vascular tissue, typical of ZC (1). Symptoms were observed in cvs. Alturas, Russet Norkotah, Pike, Ranger Russet, Umatilla Russet, and Russet Burbank. Foliar symptoms on plants that produced symptomatic tubers included purple discoloration in upper leaves, leaf rolling, axial bud elongation, chlorosis, leaf scorch, and wilt. Tissue was taken from two symptomatic tubers each of cvs. Alturas and Russet Norkotah, three tubers of cv. Umatilla Russet, and one tuber of cv. Pike. These tubers were tested by PCR for "Candidatus Liberibacter solanacearum", an unculturable alphaproteobacterium associated with ZC (1,4). Primers specific for the 16S rDNA were CLipoF (4) and OI2c (3), and primers OMB 1482f and 2086r were specific for the outer membrane protein (2). All of these samples, except one Umatilla tuber, were positive for the bacterium. The 16S rDNA and OMB amplicons from one symptomatic tuber each of Alturas (from Washington) and Pike (from Oregon) were cloned and three clones of each were sequenced. BLAST analysis of the consensus sequences confirmed "Ca. L. solanacearum". The 16S sequences (1,071 bp) from the two tubers were identical and showed 99 to 100% identity to a number of 16S rDNA sequences of "Ca. L. solanaceaum" in GenBank (e.g., Accession Nos. HM246509 and FJ957897). The 16S rDNA sequences were deposited in GenBank as Accession Nos. JN848751 and JN848753. Consensus sequences of the two OMB clones (605 bp; deposited in GenBank as Accession Nos. JN848752 and JN848754) were identical and showed 97% identity to the two "Ca. L. solanacearum" OMB sequences in GenBank (Accession Nos. CP002371 and FJ914617). Potato psyllids (Bactericera cockerelli Sulc), the vector of "Ca. L. solanacearum", were present in ZC-affected fields in Oregon and Washington and the bacterium was confirmed by PCR in 5 to 10% of 128 adult psyllids collected from two fields. On the basis of foliar and tuber symptoms, specific PCR amplification with two primer pairs, sequence analyses, and the presence of Liberibacter-infected potato psyllids, ZC and "Ca. L. solanacearum" are present in potatoes in Oregon and Washington State. Washington and Oregon together grow ~80,000 ha of potatoes. ZC has caused significant economic damage to potatoes in Texas, Mexico, Central America, and New Zealand (1). Therefore, ZC may pose a risk to agriculture in Oregon, Washington, and neighboring states. However, the potential for development of widespread and serious disease will depend upon the arrival time and number of infective potato psyllids entering the region. References: (1) J. M. Crosslin et al. Online publication. doi:10.1094/PHP-2010-0317-01-RV, Plant Health Progress, 2010. (2) J. M. Crosslin et al. Southwest. Entomol. 36:125, 2011. (3) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996. (4) G. A. Secor. Plant Dis. 93:574, 2009.
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Cultural practices and insecticide treatments and combinations were evaluated for effect on tuber damage by potato tuberworm, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) in the Columbia basin of eastern Oregon and Washington. A range of intervals between initial application of several insecticides and vine-kill were tested to determine how early to implement a program to control potato tuberworm tuber damage. Esfenvalerate, methamidophos, and methomyl were applied at recommended intervals, with programs beginning from 28 to 5 d before vine-kill. All insecticide treatments significantly reduced tuber damage compared with the untreated control, but there was no apparent advantage to beginning control efforts earlier than later in the season. Esfenvalerate and indoxacarb at two rates and a combination of the two insecticides were applied weekly beginning 4 wk before and at vine-kill, and indoxacarb was applied at and 1 wk postvine-kill as chemigation treatments. Application of insecticides at and after vine-kill also reduced tuberworm infestation. 'Russet Norkotah' and 'Russet Burbank' plants were allowed to naturally senesce or were chemically defoliated. They received either no irrigation or were irrigated by center-pivot with 0.25 cm water daily from vine-kill until harvest 2 wk later. Daily irrigation after vine-kill reduced tuber damage, and chemical vine-kill tended to reduce tuber damage compared with natural senescence. Covering hills with soil provides good protection but must be done by vine-kill. Data from these trials indicate that the most critical time for initiation of control methods is immediately before and at vine-kill.
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Control de Insectos/métodos , Insecticidas/farmacología , Mariposas Nocturnas/fisiología , Control Biológico de Vectores/métodos , Solanum tuberosum/parasitología , Agricultura , AnimalesRESUMEN
A landscape-scale study from 2004 to 2006 investigated the spatial and temporal dynamics of a new pest to the Columbia Basin of the Pacific Northwest, the potato tuberworm, Phthorimaea operculella (Zeller). Male P. operculella were monitored in spring, summer, and fall each year with a pheromone-baited trapping network in Oregon and Washington. The objectives of the study were to (1) describe the temporal and spatial dynamics of the recent outbreak of P. operculella in the region and (2) examine the relationship of the spatial and temporal distribution of the outbreak and weather (air temperature, precipitation, and dew point) and geographic variables (elevation and latitude). Weather data during the P. operculella outbreak were compared with a reference period (1993-1999) that occurred before the outbreak. The outbreak in 2004, which caused the first widespread tuber damage in the region, was positively associated with warmer temperatures in the preceding fall and in the spring, summer, and fall of the growing season. October and November 2003 and March 2004 were also drier than the reference period. However, the winter of 2003/2004 was colder than the reference period and thus mild winter conditions did not explain the outbreak. The importance of environmental variables on the seasonal spatial distribution of the pest each year was examined using nonparametric multiplicative regression. Locations with higher spring, summer, or fall temperatures were associated with increased trapping rates in most seasons. Elevation and latitude seemed to play a constraining role, because low trapping rates of P. operculella were associated with higher elevations and latitudes.
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Mariposas Nocturnas/fisiología , Solanum tuberosum/parasitología , Animales , Geografía , Masculino , Oregon , Dinámica Poblacional , Análisis de Regresión , Washingtón , Tiempo (Meteorología)RESUMEN
With the recent report of several viruses infecting garlic (Allium sativum L.) grown in the Pacific Northwest (1-3), studies were initiated on cloves planted in the fall of 2006 to determine the presence of additional viruses infecting plants exhibiting mosaic and/or chlorotic leaves. Cloves from symptomatic plants of the cultivar 'Early' from two seed production fields in Benton County, WA and two seed production fields in Morrow County, OR were tested by two-step reverse transcription (RT)-PCR using primers specific to the coat protein (CP) of the allexiviruses (4), since garlic infected with this group had similar symptoms in Asia and South America (4). Of the 87 cloves tested, 84 were positive, and four representative samples of the RT-PCR amplicons from each location were cloned and sequenced. Sequence comparisons indicated that the cloves from both locations were infected with Garlic virus D (GarV-D), also known as Japanese garlic virus (JGV), since they shared 98% identity with known isolates (GenBank Accession Nos. L388922.1, AF519572.1, and AB010303.1). In addition, sequences of isolates from the Oregon cloves shared a 96% identity with a known isolate of Garlic virus B (GarV-B; GenBank Accession No. AF543829.1). Because no antiserum specific to these viruses was available, primers specific to the CP genes of GarV-D (JGV-F2/JGV-R2 5'-GCTCACTCRGATGTGTTAGC-3' and 5'-CGCGTGGACATAAGTTGTTG-3') and GarV-B (GVB-F1/GVB-R2 5'-GAGGAGAACTAACGCCACAC-3' and 5'-ACGACCTAGCTTCCTACTTG-3') were designed and the cloves were retested by RT-PCR using these virus-specific primers. With the GarV-D specific primers, 98 and 63% of the cloves were positive from Washington and Oregon, respectively, and 52% of the cloves from Oregon were positive using the GarV-B specific primers. None of the cloves tested from Washington were positive for GarV-B. The identity of the amplicons was verified by cloning and sequencing (GarV-D, GenBank Accession No. FJ643476; GarV-B, GenBank Accession No. FJ643475). Incidence of the two viruses differed between Oregon and Washington was likely due to the expansion of the seed lots in two different locations (California and Nevada) prior to planting in 2006. With such high infection rates, studies should be conducted to determine the impact of these viruses on yield when plants are singly infected as well as in combination with the other viruses known to infect garlic in this region. These and the other viruses (1) are likely to impact yield. To our knowledge, this is the first report of GarV-D (JGV) and GarV-B in garlic in the Pacific Northwest. References: (1) S. L. Gieck et al. Plant Dis. 91:461, 2007. (2) H. R. Pappu et al. Plant Dis. 89:205, 2005 (3) H. R. Pappu et al. Online publication. doi:10.1094/PHP-2008-0919-01-RS. Plant Health Progress, 2008. (4) T. Tsuneyoshi et al. Phytopathology 86:253, 1996.
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We investigate the sulfhydryl band of cysteines as a new chromophore for two-dimensional IR (2D-IR) studies of the structure and dynamics of proteins. Cysteines can be put at almost any position in a protein by standard methods of site-directed mutagenesis and, hence, have the potential to be an extremely versatile local probe. Although being a very weak absorber in aqueous environment, the sulfhydryl group gets strongly polarized when situated in an alpha-helix inside the hydrophobic core of a protein because of a strong hydrogen bond to the backbone carbonyl group. The extinction coefficient (epsilon=150 M(-1) cm(-1)) then is sufficiently high to perform detailed 2D-IR studies even at low millimolar concentrations. Using porcine (carbonmonoxy)hemoglobin as an example, which contains two such cysteines in its wild-type form, we demonstrate that spectral diffusion deduced from the 2D-IR line shapes reports on the overall-breathing of the corresponding alpha-helix. The vibrational lifetime of the sulfhydryl group (T1 approximately 6 ps) is considerably longer than that of the much more commonly used amide I mode (approximately 1.0 ps), thereby significantly extending the time window in which spectral diffusion processes can be observed. The experiments are accompanied by molecular dynamics simulations revealing a good overall agreement.
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Hemoglobinas/química , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos de Sulfhidrilo/química , Simulación por Computador , Cisteína/química , Modelos Moleculares , Estructura Terciaria de Proteína , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Soil samples from 87 fields intended for potato production in the Columbia Basin of Washington and Oregon and 51 fields intended for mint production in Washington were assayed on a semiselective medium to quantify populations of Verticillium dahliae. The pathogen was isolated from 77 (89%) of the fields intended for potato production and 41 (80%) of the fields intended for mint production. Population densities ranged from 0 to 169 propagules/g of air-dried soil in fields intended for potato production and 0 to 75 propagules/g of air-dried soil in fields intended for mint production. Isolates of V. dahliae were recovered from soil assay plates and pure cultures were prepared to provide a collection of isolates for vegetative compatibility analysis. Among fields intended for potato production from which isolates of the fungus were assigned to a vegetative compatibility group (VCG), 93% of the fields were found to contain one or more isolates assigned to VCG 4A, nine (23%) contained one or more isolates assigned to VCG4B, and only one (3%) contained any isolates assigned to VCG 2B. In the case of fields planned for mint production in 1999 from which isolates of the fungus were assigned to a VCG, 13 fields (81%) were found to contain one or more isolates assigned to VCG 4A, 7 (44%) contained one or more isolates assigned to VCG 4B, and 5 (31%) contained one or more isolates assigned to VCG 2B. VCG 4A isolates of V. dahliae are widespread and numerous, particularly following potato production, but cause only mild to moderate symptoms in mint; therefore, this pathotype is unlikely to seriously endanger subsequent plantings of mint. However, planting potato in a field recently used to produce mint may pose a significant risk to the potato crop if high populations of the VCG4A pathotype (highly aggressive to potato) predominate. Preplant assessment of soil populations of V. dahliae without regard for the relative populations of various pathotypes present in a particular sample may lead to information not fully useful in integrated pest management systems.
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Potato is the fourth most important agricultural commodity in Michigan and is grown for table stock, chip processing, and seed. Tubers are either processed or fresh packed immediately following harvest or sent to storage. Tubers of potato cv. FL1879 representing two separate fields in Huron County were removed from separate storage facilities in February and March of 2007, and substantial internal necrosis was observed in 1 to 2% of the tubers. Symptoms included arcs similar to those caused by Tobacco rattle virus (TRV). This virus is a member of the genus Tobravirus and is transmitted by a number of species of stubby-root nematodes (Paratrichodorus or Trichodorus spp.). Stubby-root nematodes have been reported previously from Michigan (1). To confirm the presence of TRV, nucleic acid extractions were made from these symptomatic tubers (3). Samples were initially tested for TRV by reverse transcription (RT)-PCR using primers specific to the 16 kDa open reading frame on genomic RNA-1 (2). Samples from both storage facilities were positive. The 463-bp RT-PCR product, amplified with these primers, was sequenced (GenBank Accession No. EU315227) and was 99.6% identical to the corresponding region of two TRV isolates from Florida and Washington (GenBank Accession Nos. AF055912 and EU315226, respectively). In addition, sap from cv. FL1879 tuber samples was used to transmit the virus mechanically to tobacco cv. Samsun NN, which produced typical TRV symptoms following inoculation, and sap extracts from the tobacco leaves also tested positive with antiserum specific to TRV upon subsequent ELISA testing. Corky ringspot can result in substantial losses, with entire potato fields being rejected because of internal tuber damage. Once found, fields must be considered permanently at risk to this disease due to the large host range of both the virus and the nematode vector. This disease has been previously found in the United States in California, Colorado, Florida, Idaho, Washington, Oregon, and it is likely present in Indiana. To our knowledge, this is the first report of corky ringspot and TRV on potato in Michigan. References: (1) G. W. Bird and N. Knobloch. Plant Dis. Rep. 60:76, 1976. (2) J. M. Crosslin and P. E. Thomas. Am. Potato J. 72:605, 1995. (3) G. G. Presting et al. Phytopathology 85:436, 1995.
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The Columbia Basin of Oregon consists of six counties (Gilliam, Hood River, Morrow, Sherman, Wasco, and Umatilla) and is the major wheat-producing region in the state. In 2005, these counties produced 300,277 ha of mostly fall-planted wheat. While primarily a dryland production area, wheat (approximately 8,094 ha) is also grown as a rotational crop under irrigation. Stunted and chlorotic winter wheat plants with leaves exhibiting a mosaic pattern consistent with that caused by Soilborne wheat mosaic virus (SBWMV) were observed in March 2005. These plants originated from four center-pivot irrigated fields in Umatilla County with each field approximately 50.6 ha. One-half of one field was planted with cv. Western Breeders 470 (WB470) and the other half with cv. Tubbs, while the three other fields were planted to Tubbs. In the split-planted field, symptoms were widespread in the WB470 half but only observed in low-lying areas planted with Tubbs. ELISA with a monoclonal antibody (Agdia Inc., Elkhart, IN) confirmed the presence of SBWMV, which is transmitted by the soilborne organism Polymyxa graminis. Electron microscopy confirmed rigid, rod-shaped particles that were 19 nm wide and of two size classes, 138 to 222 and 416 to 471 nm long. Presence of SBWMV was further verified by reverse transcription (RT)-PCR using SBWMV RNA-2 specific primers (sense 5'-AAAGAGTCTIGCGTRTARCAYTC-3' and antisense 5'-AACGGTGTTAGTAARYTRGGKGA-3'), which amplified the predicted 338-bp product from the coat protein gene (1). Additional positive samples were found in 2006 from fall-planted wheat cvs. WB 528 and MJ9 from two additional 50.6-ha fields in Umatilla County. In 2005, yield of WB470 in the split-planted field was reduced by approximately 15% compared with yields obtained in similar fields planted with WB470 not exhibiting symptoms. SBWMV has been reported previously in Oregon (2) but nearly 322 km to the west in an area that is not the major wheat-producing region in Oregon. Because of the apparent reduced susceptibility of Tubbs, which is an older cultivar, as compared with WB470, WB528, and MJ9, which are three new high-yielding cultivars, additional research is needed to identify the reaction to SBWMV of cultivars adapted for production in the Pacific Northwest, particularly if this disease becomes widely distributed in both irrigated and dryland production areas. References: (1) G. R. G. Clover et al. Plant Pathol. 50:761, 2001. (2) M. L. Putman et al. Plant Dis. 78:102, 1994.
RESUMEN
A general mosaic and yellowing of leaves of three cultivars of garlic (Allium sativum L., Late, Early, and Germinador) were observed in two seed-production fields in Morrow County, OR in June 2005. Approximately 50% of plants within the 50-ha fields were symptomatic. With recent findings of Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV), and Garlic common latent virus (GCLV) in Washington (2), 45 composite samples of 10 leaves each from symptomatic (mosaic and yellowing) and nonsymptomatic plants were analyzed with a GCLV-specific antiserum (Agdia Inc., Elkhart, IN). All samples of 'Germinador' were infected regardless of symptoms, whereas 6.7% of all 'Late' and 'Early' samples were positive. GCLV infection was verified by reverse transcription (RT)-PCR using primers specific to the coat protein gene of GCLV followed by cloning and sequencing of the cloned amplicon. To determine the presence of a potyvirus, all composite samples were also tested with a general potyvirus antiserum (Agdia) and all samples from symptomatic plants were found to be positive. Representative positive samples from each cultivar were then tested by RT-PCR using degenerate, potyvirus group specific primers (3), and an amplicon of the expected size was obtained. To confirm which potyvirus was present, amplicons were cloned and sequenced, and sequence comparisons indicated that the representative samples were infected with OYDV. All symptomatic samples from the three cultivars were positive for OYDV when tested by RT-PCR using primers specific to its coat protein gene (1). Additionally, 53.3 and 6.7% of 'Early' and 'Late' samples, respectively, were also positive when tested with LYSV-specific primers (4). LYSV infection was further verified through cloning and sequencing of the cloned amplicon. Because this garlic is grown for seed, studies are being initiated to determine if current season spread occurs and yields are reduced. To our knowledge, this is the first report of OYDV, LYSV, and GCLV in garlic in Oregon. References: (1) P. Lunello et al. J. Virol. Methods 118:15, 2004. (2) H. R. Pappu et al. Plant Dis. 89:205, 2005. (3) S. S. Pappu et al. J. Virol. Methods 41:9, 1993. (4) T. Tsuneyoshi et al. Phytopathology. 86:253, 1996.
RESUMEN
Metam sodium (MS) is often applied to potato fields via sprinkler irrigation systems (water-run, WR) to reduce propagules of soil-borne pathogenic fungi, particularly Verticillium dahliae, to prevent yield loss from potato early dying disease. However, this procedure has not been effective for controlling quality defects in tubers caused by Columbia root-knot nematode (Meloidogyne chitwoodi). In five trials from 1996 to 2001, application of MS by soil shank injection (SH) provided better control and tuber quality than that generally obtained by WR MS, in three of five trials. Results were similar when SH MS was injected at one (41-45 cm), two (15 and 30 cm) or three (15, 30 and 45 cm) depths. In the two trials where SH metam potassium was tested, culls were reduced to 3% and 0% and were equivalent to those resulting from a similar rate in kg a.i./ha of SH MS. A shank-injected tank mix of MS plus ethoprop EC and SH MS plus in-season chemigation applications of oxamyl provided acceptable control in trials where SH MS alone was inadequate. In-furrow application of aldicarb at planting following SH MS did not appear to increase performance. Most consistent control (0-2% culled tubers in five trials) occurred when SH MS at 280 liters/ha was used together with 1,3- dichloropropene (140 liters/ha), applied simultaneously or sequentially. This was similar to combinations of 1,3-D and WR MS, but SH MS may be preferred under certain conditions.
RESUMEN
Corky ringspot disease (CRS) of potato produces necrotic areas in tubers that are considered quality defects that can lead to crop rejection. CRS is caused by tobacco rattle virus that is vectored by stubby-root nematodes (Paratrichodorus spp., Trichodorus spp.) at very low population densities, making disease management difficult and expensive. Fumigation with metam sodium (MS) is a common practice to control soil-borne fungi and increase potato yield. MS is generally applied in water via chemigation (water-run, WR) but is ineffective at controlling CRS when WR-applied, even at high rates. Therefore, WR MS is often used in combination with 1,3-dichloropropene (1,3-D), aldicarb or oxamyl to attain adequate CRS control. Between 1996 and 2000, fields with a history of CRS were treated with WR MS, shank-injected MS, and/or 1,3-D, and tubers were evaluated for symptoms of CRS. Shank injection of MS (SH MS) at depths of 41 cm, 15 and 30 cm, or 15, 30 and 45 cm controlled CRS over 3 years of testing. All rates of 280 liters/ha or greater were effective. Shank injection of metam potassium (MP) at rates of 448 liters/ha was also effective. 1,3-D controlled CRS alone or in combination with WR or SH MS. Proper shank application of MS or MP may adequately control CRS without the additional cost of other nematicides at low (<10 P. allius/250 g soil) to moderate (10 to 30 P. allius/250 g soil) populations of the nematode vector. Although SH MS was superior to WR MS, additional research is necessary to determine if this practice would be sufficient at higher CRS disease pressure or if addition of other nematicides would be necessary.
RESUMEN
Potato virus Y (PVY) is a serious potato pathogen that affects potato seed and commercial production crops. In recent decades, novel PVY strains have been described that cause necrotic symptoms on tobacco foliage and/or potato tubers. The major PVY strains that affect potato include PVY(O) and PVY(N), which have distinct serotypes that can be differentiated by immunoassay. Other economically important strain variants are derived from recombination events, including variants that cause tuber necrotic symptoms (PVY(NTN)) and PVY(O) serotypes that cause tobacco veinal necrosis (PVY(N)-W, PVY(N:O)). Although the PVY(NTN) and PVY(N)-W variants were first reported in Europe, apparently similar strains have been appearing in North America. Confirmation of the existence of these recombinant strains in North America is important, as is whether they spread from a common source or were derived by independent recombination. Whole genome sequencing can be used to positively identify strain variants and begin to address the issue of origins. Symptomology, serology, RT-PCR, and partial sequencing of the coat protein region were used to identify isolates of the PVY(NTN), PVY(N), PVY(NA-N), and PVY(N:O) for whole-genome sequencing. Sequencing confirmed the presence of PVY(NTN) and PVY(N) isolates that were >99% identical to European sequences deposited in GenBank in the 1990's. Sequences of the PVY(NA-N) and PVY(N:O) types were 99.0% and 99.5% identical to known sequences, respectively. There was no indication that recombinant strains PVY(NTN) or PVY(N:O) had different parental origins than recombinant strains previously sequenced. This is the first confirmation by whole-genome sequencing that "European"-type strain variants of PVY(N) and PVY(NTN) are present in North America, and the first reported full-length sequence of a tuber necrotic isolate of PVY(N:O).