Detection and evaluation of residual effects by defeated stripe rust resistance genes (Yr genes) in common wheat against virulent Puccinia striiformis f. sp. tritici isolates

Non-Peer ReviewedRace-specific stripe rust resistance genes (Yr genes) have been deployed into wheat cultivars against stripe rust caused by Puccinia striiformis f. sp. tritici Eriks. (Pst); however, the resistance has been quickly broken down only years after its introduction. Near isogenic lines (NILs) with defeated Yr genes were used in this study to evaluate partial non-race-specific resistance of the residual effect as possible durable resistance. The parental NILs with single Yr genes (Yr10, Yr26, Yr32) with Avocet background, F5 NILs with two Yr genes in the combinations of Yr26/Yr10, Yr32/Yr10 and Yr32/Yr26 and susceptible cultivar Avocet were inoculated with one of three Pst inoculums (W020, W049, T034+W052) virulent to all three Yr genes and infection type (IT), infection area (IA) and latent period (LP) were recorded. The same NILs were tested in stripe rust nurseries at Saskatoon, SK and Lethbridge, AB in 2018 and disease incidence and severity were recorded. The range of IT tended to be lower in NILs with Yr32/Yr10 and Yr32/Yr26 genes only with T034/W052. With different isolates, IA was reduced more often in the NILs with Yr32/Yr10 and Yr32/Yr26 genes than with Yr26/Yr10. The extension of LP correlated with reduction of IA. In disease nurseries, the natural Pst population appeared to be avirulent to Yr10 and Yr26 at both locations and the results were inconclusive. These results from growth chamber experiments suggest that residual effect by defeated Yr genes possibly exists in certain combinations

Effect of Concussion on Clinically Measured Reaction Time in 9 NCAA Division I Collegiate Athletes: A Preliminary Study

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147005/1/pmr2212.pd

Characterization of flax germplasm for resistance to fusarium wilt

Non-Peer ReviewedFusarium wilt of flax (Linum usitatissimum L.) caused by Fusarium oxysporum f. sp. lini (Fol) is an economically important disease that can result in severe yield losses. Due to the pathogen’s ability to survive in soil for long periods, it is essential to identify fusarium wilt resistant flax varieties. The objectives of the study were to phenotype and compare a recombinant inbred line (RIL) population of flax in a controlled environment and in field wilt nurseries. Disease reaction of a subset (160) of RIL lines developed from cultivars ‘Aurore’ (moderately resistant) and ‘Oliver’ (susceptible) was assessed under controlled environment conditions to two Fol isolates. Disease severity was determined and the area under the disease progress curve (AUDPC) was calculated. The population varied in response from resistant to highly susceptible, indicating that resistant to wilt was probably polygenic. Twenty-eight days after inoculation, 14% and 5% of the RILs were severely wilted (scores of 8 and 9, with isolates 131 and 81, respectively). Plant height was negatively correlated with AUDPC (r2= -0.13155 for 131 and r2=-0.29841 for 81). Similarly, in the field in wilt nurseries, at Saskatoon and Morden, evaluation of the full set of 200 RILs, the disease reaction varied from resistant to susceptible, with 21% and 42% of RILs severely wilted (rated 8 and 9) at each site at the green boll stage. The results from the two locations were significantly different, although moderately correlated (r2=0.6127). The 160 RILs in controlled environment inoculated with isolates 131 and 81 showed a higher correlation for disease severity at 28 days after inoculation, with the wilt nursery in Saskatoon (r= 0.40028 and r2=0.38046) as compared to Morden (r2=0.33016 and r2=0.21140) at green boll stage. Differences in environmental and experimental conditions (such as seeding date) at the two locations, as well as different Fol strains in the soil combined with the subjectivity of the grading system may explain the differences between locations

Gender Issues in Clinical Dental Education

In spring 2011, a study was initiated to investigate the nature and extent of gender issues in clinical dental education at the University of North Carolina at Chapel Hill School of Dentistry. Surveys were sent to 236 dental students in the second, third, and fourth years; eighty-six (36.4 percent) responded. Surveys were also sent to seventy-one full-time dental faculty members who had clinical contact with students, and thirty-four (47.9 percent) responded. Of the student respondents, fifty-one were female and thirty-five were male; the faculty respondents were ten women and twenty-four men. A significantly greater proportion of female than male student respondents reported that issues related to gender affected clinical training. The female students also responded that mentorship was less available and less in content for them compared to males, and significantly more female than male students reported lower self-confidence in clinical settings. Among faculty respondents, a higher proportion of women than men reported insufficient awareness of gender issues. These faculty members also reported thinking that female students showed more empathy toward patients than males. Both faculty and student respondents said that female faculty members received less respect from students than did male faculty members. Forty-eight percent of the students reported experiencing or witnessing gender-based prejudice in clinical settings, and 7.0 percent reported experiencing or witnessing unwelcome sexual advances or conduct. A more robust study to include other dental institutions is needed. With confirmation of specific gender issues, corrective measures could be recommended to improve the climate for both females and males in the clinical component of dental education

A method for incorporating organ motion due to breathing into 3D dose calculations

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134856/1/mp8577.pd

Mitigating the risk of blackleg disease of canola using fungicide strategies

Non-Peer ReviewedBlackleg, the most widespread disease on canola on the prairies, has been managed mainly through use of resistant cultivars in combination with crop rotation. Over the past few years, crop rotation has been tightened in favor of canola production due largely to profitability considerations but this practice can speed up changes in pathogen race structure that may lead to losses of resistance for some of the current canola cultivars. In this study, fungicides strategies were assessed as a second line of defense for control of blackleg and canola yield benefit in case when the variety resistance is overcome by the pathogen. In 2011, the fungicide Headline, Quadris, and Quilt were applied at 2-4 leaf stage and/or bolting to target varying periods of infection at three locations on the prairies. On the susceptible cultivar Westar, an early application (2-4 leaf) of Headline or Quadris reduced the disease at Carman, MB, but not at Melfort or Vegreville relative to non-treated controls. None of the fungicide treatments increased canola yield substantially either. The study will be continued for two more years at multiple locations across the prairies

Assessing the genetic and pathogenic variability of Pyrenophora teres f. maculata (spot form net blotch of barley) and its ability to overcome currently-used sources of resistance on the Canadian prairies

Non-Peer ReviewedEighty two isolates of the fungus Pyrenophora teres f. maculata, causal agent of spot form net blotch (SFNB) of barley, were collected across the Canadian prairies. Following genetic analysis using 13 microsatellite DNA markers, 27 isolates were selected to assess the degree of pathogenic variation in the fungus. Pathogenic variability was evaluated by inoculating isolates onto 11 barley genotypes as differential hosts at the seedling stage. One week following inoculation, the second and third leaves of each plant were rated on to a 1–9 disease severity scale, and plants with scores of 1–3 and >3 were scored as resistant and susceptible, respectively. The entire experiment was repeated. Cluster analysis revealed 13 distinct pathotype groups (virulence patterns) among the 27 representative isolates. Disease severity ratings ranged from 2.2 to 6.1 with a mean of 4.6. To assess the risk of resistance breakdown, the resistance of four barley cultivars (‘AAC Synergy’, ‘CDC Meredith’, ‘Cerveza’ and ‘Major’), which had been previously identified as resistant to SFNB on the Canadian prairies, was evaluated at the seedling stage against six isolates of P. teres f. maculata representing four different pathotypes. The resistance in ‘CDC Meredith’ was clearly overcome by all isolates tested, while ‘AAC Synergy’, ‘Cerveza’ and ‘Major’ still exhibited resistance against all of the pathotypes. The identification of fungal isolates virulent on ‘CDC Meredith’ suggests that producers should avoid growing the same resistant barley variety in short rotation, and avoid relying on resistance as the sole approach to disease management. Judicious use of fungicides, coupled with rotations of at least two years between barley crops and diversity in the barley varieties grown, will promote effective and sustainable management of spot form net blotch

3-Year Comparison of Drug-Eluting Versus Bare-Metal Stents

ObjectivesThe aim of this study was to compare 3-year cumulative outcomes to landmark second- and third-year outcomes with the routine use of drug-eluting stents (DES) (>75% “off-label”) with a comparable group treated with bare-metal stents (BMS).BackgroundLong-term safety concerns after “off-label” DES use persist, despite recent 2-year data showing comparable safety to BMS use.MethodsClinical outcomes (nonfatal myocardial infarction, all-cause mortality) were assessed in 1,147 consecutive patients who received a BMS in the year before the introduction of DES at Wake Forest University Baptist Medical Center and 1,246 consecutive patients that received a DES after it became our routine choice with equivalent complete 3-year follow-up.ResultsStents were used for “off-label” indications in 80% of DES patients. At 3 years, the hazard ratio for DES compared with BMS for cumulative target vessel revascularization was 0.65 (95% confidence interval [CI]: 0.51 to 0.82), nonfatal myocardial infarction or death was 0.85 (95% CI: 0.71 to 1.03), and all-cause mortality 0.80 (95% CI: 0.64 to 1.01). The DES clinical benefits occurred entirely within the first year, with similar rates of these clinical end points in the second and third year. The cumulative hazard ratio of stent thrombosis DES compared with BMS was 1.07 (95% CI: 0.57 to 2.01), with similar rates of stent thrombosis in the third year (p = 0.70).ConclusionsThe routine clinical use of DES for “off-label” indications was associated with lower clinical end points at 3 years than treatment with BMS in a comparable group of patients, with similar cumulative rates of stent thrombosis. There was no evidence of late “catch-up” of adverse DES events

Inclusion of organ deformation in dose calculations

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135079/1/mp9039.pd