scholarly journals Phenological Variation in Bluebunch Wheatgrass (Pseudoro-Egneria Spicata): Implications for Seed Sourcing, Harvest, and Restoration

Land ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1064
Author(s):  
Kathryn Prive ◽  
Matthew R. Orr ◽  
Francis F. Kilkenny ◽  
Ronald J. Reuter ◽  
Holly R. Prendeville

To reduce maladaptation in cultivated seed lots, seed transfer zones (STZs) have been developed for grasslands and other habitats using morphological traits and phenological measurements that only capture the first day of events such as flowering and seed ripening. Phenology is closely linked to plant fitness and may affect genetic loss during harvests of seed raised for ecological restoration. Here, we measured the detailed phenologies of 27 populations from six STZs of bluebunch wheatgrass (Pseudoroegneria spicata) (Pursh) Á. Löve (Poaceae) raised in a common garden to test whether existing STZs created using a combination of plant morphology and “first-day” phenological measurements adequately capture population-level variation in season-long, detailed phenologies. We also used detailed phenologies to test whether genetic losses may occur during single-pass harvests of commercial seed. Mixed and random effect models revealed differences in detailed reproductive phenology among populations within two of six STZs. The number of individual plants within an STZ not producing harvestable seed during peak harvest levels indicated that 10–27% of individuals from a seed lot could be excluded from a single-pass harvest. Although our findings generally support current STZ delineations for P. spicata, they point to the possible precautionary importance of sourcing from multiple populations and harvesting with multiple passes when resources permit.

CJEM ◽  
2020 ◽  
Vol 22 (S1) ◽  
pp. S38-S38
Author(s):  
K. de Wit ◽  
D. Nishijima ◽  
S. Mason ◽  
R. Jeanmonod ◽  
S. Parpia ◽  
...  

Introduction: It is unclear whether anticoagulant or antiplatelet medications increase the risk for intracranial bleeding in older adults after a fall. Our aim was to report the incidence of intracranial bleeding among older adults presenting to the emergency department (ED) with a fall, among patients taking anticoagulants, antiplatelet medications, both medications and neither medication. Methods: This was a systematic review and meta-analysis, PROSPERO reference CRD42019122626. Medline, EMBASE (via OVID 1946 - July 2019), Cochrane, Database of Abstracts of Reviews of Effects databases and the grey literature were searched for studies reporting on older adults who were evaluated after a fall. We included prospective studies conducted in the ED where more than 80% of the cohort were 65 years or older and had fallen. We contacted study authors for aggregate data on intracranial bleeding in patients prescribed anticoagulant medication, antiplatelet medication and neither medication. Incidences of intracranial bleeding were pooled using random effect models, and I2 index was used to assess heterogeneity. Results: From 7,240 publication titles, 10 studies met inclusion criteria. The authors of 8 of these 10 studies provided data (on 9,489 patients). All studies scored low or moderate risk of bias. The pooled incidence of intracranial bleeding among patients taking an anticoagulant medication was 5.1% (n = 5,016, 95% Confidence Interval (CI): 4.1 to 6.3%) I2 = 42%, a single antiplatelet 6.4% (n = 2,148, 95% CI: 5.4 to 7.6%) I2 = 75%, both anticoagulant and antiplatelet medications 5.9% (n = 212, 95% CI: 1.3 to 13.5%) I2 = 72%, and neither of these medications 4.8% (n = 1,927, 95% CI: 3.5 to 6.2%) I2 = 50%. A sensitivity analysis restricted to patients who had a head CT in the ED reported incidences of 6.1% (n = 3,561, 95% CI: 3 to 8.3%), 8.4% (n = 1,781, 95% CI: 5.5 to 11.8%), 6.7% (n = 206, 95% CI 1.5 to 15.2%) and 6.6% (n = 1,310, 95% CI: 5.0 to 8.4%) respectively. Conclusion: The incidence of fall-related intracranial bleeding in older ED patients was similar among patients who take anticoagulant medication, antiplatelet medication, both and neither medication, although there was heterogeneity between study findings.


2019 ◽  
Vol 74 (3) ◽  
pp. 251-256 ◽  
Author(s):  
Hailong Su ◽  
Guo Zhang

Background: The correlation between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and hepatocellular carcinoma (HCC) remains controversial. Objectives: We performed this study to better assess the relationship between MTHFR gene polymorphisms and the likelihood of HCC. Methods: A systematic research of PubMed, Medline, and Embase was performed to retrieve relevant articles. ORs and 95% CIs were calculated. Results: A total of 15 studies with 8,378 participants were analyzed. In overall analyses, a significant association with the likelihood of HCC was detected for the rs1801131 polymorphism with fixed-effect models (FEMs) in recessive comparison (p = 0.002, OR 0.62, 95% CI 0.43–0.82). However, no positive results were detected for the rs1801133 polymorphism in any comparison. Further subgroup analyses revealed that the rs1801131 polymorphism was significantly associated with the likelihood of HCC in Asians with both FEMs (recessive model: p < 0.0001, OR 0.42, 95% CI 0.29–0.62; allele model: p = 0.004, OR 1.20, 95% CI 1.06–1.35) and random-effect models (recessive model: p = 0.002, OR 0.47, 95% CI 0.29–0.75). Nevertheless, we failed to detect any significant correlation between the rs1801133 polymorphism and HCC. Conclusions: Our findings indicated that the rs1801131 polymorphism may serve as a genetic biomarker of HCC in Asians.


2012 ◽  
Vol 109 ◽  
pp. 146-155 ◽  
Author(s):  
James O. Chipperfield ◽  
David G. Steel

Author(s):  
Xiaoting Wu ◽  
Min Zhang ◽  
Richard L Prager ◽  
Donald S Likosky

Introduction: A number of statistical approaches have been advocated and implemented to estimate adjusted hospital outcomes for public reporting or reimbursement. Nonetheless, the ability of these methods to identify hospital performance outliers in support of quality improvement has not yet been fully investigated. Methods: We leveraged data from patients undergoing coronary artery bypass grafting surgery between 2012-2015 at 33 hospitals participating in a statewide quality collaborative. We applied 5 different statistical approaches (1: indirect standardization with standard logistic regression models, 2: indirect standardization with fixed effect models, 3: indirect standardization with random effect models, 4: direct standardization with fixed effect models, 5: direct standardization with random effect models) to estimate hospital post-operative pneumonia rates adjusting for patients’ risk. Unlike the standard logistic regression models, both fixed effect and random effect models accounted for hospital effect. We applied each method to each year, and subsequently compared methods in their ability to identify hospital performance outliers. Results: Pneumonia rates ranged from 0 % to 24 %. The standard logistic regression models for 2013-2015 had c-statistics of 0.73-0.75, fixed effect models had c-statistics of 0.81-0.83, and random effect models had c-statistics of 0.80-0.83. Each method differed in its ability to identify performance outliers (Figure 1). In direct standardization, random effect models stabilized the hospital rates by moving the estimated rates toward the average rate, fixed effect models produced larger standard errors of hospital effect (particularly for hospitals with low case volumes). In indirect standardization, the three models showed high agreement on their derived observed: expected ratio (intraclass correlation =0.95). Indirect standardization with fixed effect or random effect models, identified similar hospital performance outliers in each year. Conclusion: The five statistical approaches varied in their ability to identify performance outliers. Given its higher sensitivity to outlier hospitals, indirect standardization methods with fixed or random effect models, may be best suited to support quality improvement activities.


1990 ◽  
Vol 68 (8) ◽  
pp. 1780-1787 ◽  
Author(s):  
Denise M. Seliskar

Scirpus americanus Pers., a major dune slack plant in coastal sand dune ecosystems, differs in height along transects ranging between the lowest and highest elevational areas of slacks located along the coast of Delaware, U.S.A. Using reciprocal transplant and common garden experiments, results suggest that environmental factors rather than hereditary traits are more important in accounting for the differences in plant morphology expressed in the field. Dune slack plants are exposed to stresses of waterlogging and sand accretion in their natural environment. In controlled greenhouse experiments waterlogging was shown to inhibit stem growth and cause an increase in aerenchymatous tissue, whereas periodic sand deposition caused an increase in the plant height of Scirpus.


Author(s):  
Juul H. D. Henkens ◽  
Matthijs Kalmijn ◽  
Helga A. G. de Valk

AbstractLife satisfaction is crucial for healthy development into adulthood. However, it is yet largely unknown how life satisfaction develops in the transition to adulthood. This study examined life satisfaction development in this transition and paid special attention to differences between boys, girls, children of immigrants, and nonimmigrants. Unique longitudinal data of seven waves (2010–2018) of the Children of Immigrants Longitudinal Survey Germany were used. Respondents (N = 3757, 54% girls, 78% nonimmigrants, Mage weighted = 14.6, SD = 0.6 at wave 1) were followed between ages 14 and 23 and multi-level random effect models were applied. Life satisfaction developed in a nonlinear way in the transition to adulthood (M-shape), with overall decreases between age 17 and 18 and between age 20 and 23. Girls reported lower life satisfaction levels in adolescence and more unstable trajectories than boys, where girls with immigrant backgrounds represented the least advantageous life satisfaction trajectory. Differences in life satisfaction between groups decreased from age 19 onwards.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5746 ◽  
Author(s):  
Verena Tams ◽  
Jennifer Lüneburg ◽  
Laura Seddar ◽  
Jan-Phillip Detampel ◽  
Mathilde Cordellier

Phenotypic plasticity is the ability of a genotype to produce different phenotypes depending on the environment. It has an influence on the adaptive potential to environmental change and the capability to adapt locally. Adaptation to environmental change happens at the population level, thereby contributing to genotypic and phenotypic variation within a species. Predation is an important ecological factor structuring communities and maintaining species diversity. Prey developed different strategies to reduce their vulnerability to predators by changing their behaviour, their morphology or their life history. Predator-induced life history responses inDaphniahave been investigated for decades, but intra-and inter-population variability was rarely addressed explicitly. We addressed this issue by conducting a common garden experiment with 24 clonal lines of EuropeanDaphnia galeataoriginating from four populations, each represented by six clonal lines. We recorded life history traits in the absence and presence of fish kairomones. Additionally, we looked at the shape of experimental individuals by conducting a geometric morphometric analysis, thus assessing predator-induced morphometric changes. Our data revealed high intraspecific phenotypic variation within and between fourD. galeatapopulations, the potential to locally adapt to a vertebrate predator regime as well as an effect of the fish kairomones on morphology ofD. galeata.


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