The impact of ash dieback on veteran trees in southwestern Sweden

Ash dieback (Hymenoscyphus fraxineus) is a fungal disease which affects ash throughout Sweden. Monitoring to study of the impact of ash dieback on veteran trees was undertaken in southwest Sweden in 2009, 2011, 2013, 2015, and 2020. The study found that 94.5% of the ash trees observed were affected by ash dieback disease in 2020 compared with 62% in 2009. 70 of the studied ash trees have died (21%) since the monitoring began. In 2009 there was no relationship between girth and ash dieback, but in 2020 the correlation between girth and the impact of ash dieback was statistically significant. In 2020, also for the first time during monitoring, the ash trees in the shade were significantly more affected by ash dieback, compared with trees standing in the open. This difference was not detected in 2013 or 2015. The effect of ash dieback on pollarded trees has varied between the years studied, but in 2020 there is no longer any significant difference between the pollarded and the non-pollarded ash trees. There was however a significant difference in the mortality rates between the groups of trees, with ash trees pollarded in more recent times having the highest mortality. Therefore, the recommendation in relation to veteran trees with ash dieback is that all pruning on veteran ash trees should be avoided. Pollarding should only be done on ash pollards that are in a regular cutting cycle and are not showing any symptoms of ash dieback. If possible, clear around old ash trees if they are in shaded conditions. Given that there are relatively few studies on the impact of ash dieback on veteran ash trees, the results of this study should also be relevant outside of Sweden and for the management of ash trees in non-woodland situations. Key words: Ash dieback, pollards, veteran trees, Hymenoscyphus fraxineus, ash

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Will natural resistance result in populations of ash trees remaining in British woodlands after a century of ash dieback disease?

Royal Society Open Science ◽

10.1098/rsos.190908 ◽

2019 ◽

Vol 6 (8) ◽

pp. 190908

Author(s):

Matthew R. Evans

Keyword(s):

Population Size ◽

Host Species ◽

Natural Resistance ◽

Ash Dieback ◽

Pests And Diseases ◽

Ash Trees ◽

High Heritability ◽

Dieback Disease ◽

The Impact ◽

Selective Breeding Programme

Novel pests and diseases are becoming increasingly common, and often cause additional mortality to host species in the newly contacted communities. This can alter the structure of the community up to, and including, the extinction of host species. In the last 20 years, ash dieback (ADB) disease has spread into Europe from East Asia. It has caused substantial mortality in ash tree ( Fraxinus excelsior L . ) populations. However, a proportion of the individuals in most populations appear to be less susceptible to ADB and resistance seems to have high heritability. These observations have led to suggestions that ash populations may be sustainable after the disease. In order to test this hypothesis, I modified an existing model of UK woodland (parametrized for Wytham Woods, Oxfordshire) to take into account the impact of ADB and allowed offspring to inherit resistance traits from their parent. The results suggest that ash populations would still exist in 100 years, but at lower levels than they are currently. For example, when the initial proportion of resistant individuals is about 10% and heritability of resistance is 0.5, then the population of ash falls to about one-third of present levels. The proportion of individuals initially resistant to ADB had a larger effect on population size after 100 years than the heritability of resistance. The fact that the initial size of the resistant population is important to achieve a high population size in the presence of ADB suggests that a selective breeding programme with the intention of augmenting the natural ash populations would be beneficial.

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Spread and Severity of Ash Dieback in Switzerland – Tree Characteristics and Landscape Features Explain Varying Mortality Probability

Frontiers in Forests and Global Change ◽

10.3389/ffgc.2021.645920 ◽

2021 ◽

Vol 4 ◽

Author(s):

Stefan Klesse ◽

Meinrad Abegg ◽

Sven E. Hopf ◽

Martin M. Gossner ◽

Andreas Rigling ◽

...

Keyword(s):

Mortality Rates ◽

National Forest Inventory ◽

Mean Annual Precipitation ◽

Soil Conditions ◽

Comprehensive Overview ◽

Ash Dieback ◽

Rate Dependent ◽

Hymenoscyphus Fraxineus ◽

Mortality Probability ◽

Ash Trees

Since the 1990s the invasive fungus Hymenoscyphus fraxineus has been threatening European ash (Fraxinus excelsior), a tree species with high ecological and economic importance. This pathogen is causing severe crown dieback, leading to high mortality rates across Europe and is present in Switzerland since 2008. In this study, we provide a comprehensive overview of the temporal evolution of crown damage and mortality rates in Switzerland over the 2009–2019 period. Harnessing the power of the annualized design of the Swiss national forest inventory (NFI), we show that annual mortality rates (AMRs) of ash increased significantly since the arrival of the fungus, with stronger effects in small trees [<26 cm diameter at breast height (DBH)]. Mortality modeling confirmed a size and growth-rate dependent mortality probability (MP). It also revealed that stands with higher humidity – either through higher mean annual precipitation or more humid soil conditions – showed also increased MP. Decreasing host abundance with increasing elevation was also associated with lower MP. Special ash surveys performed over the last 10 years still show a large percentage of ash trees with very low defoliation. This gives hope to finding possible tolerant or resistant trees for (inter-)national breeding programs. In the mean-time our results reinforce previously published management guidelines to promote not only healthy big trees, but also healthy and fast-growing young trees in more open stands for long-term conservation of ash in Europe.

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Patients Who Attend Alone at a First Memory Consultation: Are They a Specific Population,or Is It an Instance of Confounding Bias?

European Neurology ◽

10.1159/000500483 ◽

2019 ◽

Vol 81 (1-2) ◽

pp. 81-86

Author(s):

Pierre Koskas ◽

Mouna Romdhani ◽

Olivier Drunat

Keyword(s):

Selection Bias ◽

Confounding Bias ◽

Significant Difference ◽

Comparison Groups ◽

Methodological Problems ◽

Group 2 ◽

The Impact ◽

First Time ◽

State Examination ◽

Group 1

As commonly happens in epidemiological research, none of the reported studies were totally free of methodological problems. Studies have considered the influence of social relationships on dementia, but the mechanisms underlying these associations are not perfectly understood. We look at the possible impact of selection bias. For their first memory consultation, patients may come alone or accompanied by a relative. Our objective is to better understand the impact of this factor by retrospective follow-up of geriatric memory outpatients over several years. All patients over 70 who were referred to Bretonneau Memory Clinic for the first time, between January 2006 and 2018, were included in the study. The patients who came alone formed group 1, the others, whatever type of relative accompanied them, formed group 2. We compared the Mini-Mental State Examination (MMSE) scores of patients; and for all patients who came twice for consultation with at least a 60-day interval, we compared their first MMSE with the MMSE performed at the second consultation. In total, 2,935 patients were included, aged 79.7 ± 8.4 years. Six hundred and twenty-five formed group 1 and 2,310 group 2. We found a significant difference in MMSE scores between the 2 groups of patients; and upon second consultation in group 2, but that difference was minor in group 1. Our finding of a possible confounding factor underlines the complexity of choosing comparison groups in order to minimize selection bias while maintaining clinical relevance.

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Assessing Genotypic and Environmental Effects on Endophyte Communities of Fraxinus (Ash) Using Culture Dependent and Independent DNA Sequencing

Journal of Fungi ◽

10.3390/jof7070565 ◽

2021 ◽

Vol 7 (7) ◽

pp. 565

Author(s):

Anindita Lahiri ◽

Brian R. Murphy ◽

Trevor R. Hodkinson

Keyword(s):

Community Composition ◽

Environmental Effects ◽

High Throughput Sequencing ◽

Fungal Community Composition ◽

Species Identity ◽

Ash Dieback ◽

Hymenoscyphus Fraxineus ◽

Culture Independent ◽

The Impact ◽

Culture Dependent

Fraxinus excelsior populations are in decline due to the ash dieback disease Hymenoscyphus fraxineus. It is important to understand genotypic and environmental effects on its fungal microbiome to develop disease management strategies. To do this, we used culture dependent and culture independent approaches to characterize endophyte material from contrasting ash provenances, environments, and tissues (leaves, roots, seeds). Endophytes were isolated and identified using nrITS, LSU, or tef DNA loci in the culture dependent assessments, which were mostly Ascomycota and assigned to 37 families. Few taxa were shared between roots and leaves. The culture independent approach used high throughput sequencing (HTS) of nrITS amplicons directly from plant DNA and detected 35 families. Large differences were found in OTU diversity and community composition estimated by the contrasting approaches and these data need to be combined for estimations of the core endophyte communities. Species richness and Shannon index values were highest for the leaf material and the French population. Few species were shared between seed and leaf tissue. PCoA and NMDS of the HTS data showed that seed and leaf microbiome communities were highly distinct and that there was a strong influence of Fraxinus species identity on their fungal community composition. The results will facilitate a better understanding of ash fungal ecology and are a step toward identifying microbial biocontrol systems to minimize the impact of the disease.

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DAMPAK KRISIS GLOBAL TERHADAP NON PERFORMING LOAN BANK DEVISA NASIONAL

Inovbiz: Jurnal Inovasi Bisnis ◽

10.35314/inovbiz.v4i2.72 ◽

2016 ◽

Vol 4 (2) ◽

pp. 81

Author(s):

Suharyono Suharyono ◽

Teguh Widodo

Keyword(s):

Key Words ◽

Foreign Exchange ◽

T Test ◽

Global Crisis ◽

Significant Difference ◽

Before And After ◽

Composite Rating ◽

The Impact

Abstract: The global crisis has resulted non performing loan (NPL) increased. The measurement of the banks non performing loan ratio is applicable to assess the composite rating of a bank, as the impact of the global crisis toward non performing loan of foreign exchange banks. This study aimed to determine whether there was significant difference between foreign exchange banks non- performing loan before and after the global crisis. The Bank’s non performing loans was measured by comparing the Non-Performing Loan to the total credit. The population of this study was 35 foreign exchange banks. The Hypothesis was tested by using Mann Whitney different test and Independent Sample T Test. The research of this study showed that non performing loan of foreign exchange banks before, during, and after global crisis did not have significant difference. Key words: NPL, Bank, Foreign Exchange, Crisis, global.

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Preoperative endoscopic biliary stenting before pancreatico duodenectomy: Does timing matter?

10.21203/rs.3.rs-37972/v1 ◽

2020 ◽

Author(s):

Abu Bakar Hafeez Bhatti ◽

Roshni Zahra Jafri ◽

M Kashif Khan ◽

Faisal Saud Dar

Keyword(s):

Obstructive Jaundice ◽

Hospital Stay ◽

Mortality Rates ◽

Infectious Complications ◽

Wound Infections ◽

Biliary Stenting ◽

Endoscopic Biliary Stenting ◽

Significant Difference ◽

The Impact ◽

Surgery Duration

Abstract BackgroundRole of preoperative biliary stenting (PBS) before pancreaticodoudenectomy (PD) in patients with obstructive jaundice is debatable. The objective of the current study was to assess outcomes after PD in patients who underwent upfront surgery or PBS and determine the impact of stent to surgery duration on outcomes after PD. Methods We reviewed 147 patients who underwent PD between 2011 and 2019. Patients were grouped based on whether they underwent upfront surgery (N=76) or PBS (N=71). We further assessed outcomes based on stent to surgery interval < 4 weeks or > 4 weeks. We looked at 30 and 90 day morbidity and mortality rates in these patients.Results A significant increase in wound infections (7% vs 25%)(P=0.003), overall infectious complications (22.5% vs 38.1%)(P=0.04), re admissions (0 vs 10.5%)(P=0.005) and hospital stay (9 vs 10 days)(P=0.006) was seen in the PBS group. There was no significant difference in 30 day mortality (2.8 % vs 6.5%)(P=0.4). When compared with upfront surgery group, patients with stent to surgery duration > 4 weeks had higher rates of wound infection (7% vs 29%)(P=0.009), sepsis (11.2% vs 29%)(P=0.02), overall infectious complications (22.5% vs 45.1%)(P=0.02), re admissions (0 vs 12.9%) (P=0.007) and hospital stay (9 vs 10 days)(P=0.03). The lowest rate of infectious complications was seen when PD was performed within 2 weeks (22.2%) or 6-8 weeks (12.5%) after stenting. None of the patients with stent-surgery duration < 2 weeks developed sepsis. ConclusionsPBS appears to increase infection related morbidity after PD. In patients with PBS, low morbidity is seen with early (< 2 weeks) and delayed PD (6-8weeks).

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Estimating mortality rates of European ash ( Fraxinus excelsior ) under the ash dieback ( Hymenoscyphus fraxineus ) epidemic

Plants People Planet ◽

10.1002/ppp3.11 ◽

2018 ◽

Vol 1 (1) ◽

pp. 48-58 ◽

Cited By ~ 27

Author(s):

Tim L. R. Coker ◽

Jiří Rozsypálek ◽

Anne Edwards ◽

Tony P. Harwood ◽

Louise Butfoy ◽

...

Keyword(s):

Mortality Rates ◽

Fraxinus Excelsior ◽

Ash Dieback ◽

Hymenoscyphus Fraxineus ◽

European Ash

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Lessons from the Frontline: Exploring How Stakeholders May Respond to Emerald Ash Borer Management in Europe

Forests ◽

10.3390/f11060617 ◽

2020 ◽

Vol 11 (6) ◽

pp. 617 ◽

Cited By ~ 1

Author(s):

Mariella Marzano ◽

Clare Hall ◽

Norman Dandy ◽

Cherie LeBlanc Fisher ◽

Andrea Diss-Torrance ◽

...

Keyword(s):

Biological Control ◽

Social Acceptance ◽

Emerald Ash Borer ◽

Social Acceptability ◽

Ash Dieback ◽

Hymenoscyphus Fraxineus ◽

The Social ◽

Ash Trees ◽

The Usa ◽

Management Approaches

The emerald ash borer (EAB) has caused extensive damage and high mortality to native ash trees (Fraxinus; sp.) in North America. As European countries battle with the deadly pathogen Hymenoscyphus fraxineus (ash dieback) affecting European ash (Fraxinus excelsior), there is concern that the arrival of EAB will signal the demise of this much-loved tree. While Europe prepares for EAB it is vital that we understand the social dimensions that will likely influence the social acceptability of potential management measures, and experiences from the USA can potentially guide this. We draw on differing sources including a literature review, documentary analysis, and consultation with key informants from Chicago and the Twin Cities of Minneapolis and St. Paul. In this paper, we focus on EAB management responses that involve chemical applications, tree felling and replanting, and biological control, and assess their likely social acceptability to stakeholders based on the perceived risks and benefits. Benefits involve protecting specific ash trees and slowing the spread of EAB across the landscape. Risks include collateral harm from insecticide use on human and environmental health, financial costs and liabilities, and the effectiveness of each approach. Biological control and replacing ash with other species are likely to be largely acceptable across contexts and stakeholder groups but pre-emptive felling and insecticide application could be more problematic if seeking widespread social acceptance. Based on our observations from the evidence collected we offer suggestions for approaching EAB management in Europe with a focus on improving prospects of social acceptability. Strong engagement will be necessary to establish the relevance and reason for using different management approaches and to build awareness and trust.

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Mortality Rates do not Differ among Patients Prescribed Various Vitamin d Agents

Peritoneal Dialysis International ◽

10.3747/pdi.2012.00324 ◽

2015 ◽

Vol 35 (1) ◽

pp. 62-69 ◽

Cited By ~ 3

Author(s):

T. Christopher Bond ◽

Steve Wilson ◽

John Moran ◽

Mahesh Krishnan

Keyword(s):

Vitamin D ◽

Peritoneal Dialysis ◽

Proportional Hazards Model ◽

Mortality Rates ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Dialysis Patients ◽

Oral Vitamin ◽

Significant Difference ◽

The Impact

BackgroundLimited well-controlled research exists examining the impact of different formulations of oral vitamin D on clinical outcomes in dialysis patients, specifically those on peritoneal dialysis. For this retrospective mortality analysis, we compared mortality rates of patients on 3 of the most commonly prescribed vitamin D agents.MethodsWe examined 2 years (7/1/2008 to 6/30/2010) of oral medication records of peritoneal dialysis patients from a large US dialysis organization. Patients were identified whose physicians prescribed a single form of vitamin D (calcitriol, paricalcitol, or doxercalciferol) for ≥ 90% of all patient-months. We excluded incident patients (< 90 days on dialysis) and patients whose physicians treated < 5 peritoneal dialysis patients at a dialysis facility, and we assessed mortality.ResultsThe analysis inclusion criteria identified 1,707 patients. The subset in this analysis included 12.6% of all prevalent peritoneal dialysis patients and 11.8% of prevalent patient-months. Patients with physicians who predominately prescribed calcitriol had a lower mortality rate: 9.33 (confidence interval (CI) 7.06, 11.60) deaths per 100 patient-years than the doxercalciferol, 12.20 (CI 9.34, 15.06) or paricalcitol, 12.27 (CI 9.27, 15.28) groups. However, these differences were not statistically significant. A Cox proportional hazards model, adjusting for differences in age, vintage, gender, race, body mass index, and comorbidities also showed no significant differences.ConclusionsFor this peritoneal dialysis population, instrumental variable analyses showed no significant difference in mortality in patients taking the most common oral vitamin D formulations (calcitriol, doxercalciferol, paricalcitol).

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Amplifying feedback loop between growth and wood anatomical characteristics of Fraxinus excelsior explains size-related susceptibility to ash dieback

Tree Physiology ◽

10.1093/treephys/tpaa091 ◽

2020 ◽

Cited By ~ 1

Author(s):

Stefan Klesse ◽

Georg von Arx ◽

Martin M Gossner ◽

Christian Hug ◽

Andreas Rigling ◽

...

Keyword(s):

Landscape Heterogeneity ◽

Turgor Pressure ◽

Ring Width ◽

Mortality Rates ◽

Data Availability ◽

Fraxinus Excelsior ◽

Ash Dieback ◽

Vessel Size ◽

Hymenoscyphus Fraxineus ◽

Crown Dieback

Abstract Since the 1990s the invasive fungus Hymenoscyphus fraxineus has caused severe crown dieback and high mortality rates in Fraxinus excelsior in Europe. In addition to a strong genetic control of tolerance to the fungus, previous studies have found landscape heterogeneity to be an additional driver of variability in the severity of dieback symptoms. However, apart from climatic conditions related to heat and humidity influencing fungal infection success, the mechanistic understanding of why smaller or slower-growing trees are more susceptible to dieback remains less well understood. Here, we analyzed three stands in Switzerland with a unique setting of 8 years of data availability of intra-annual diameter growth and annual crown health assessments. We complemented this by ring width and quantitative wood anatomical measurements extending back before the monitoring started to investigate if wood anatomical adjustments can help better explain the size-related dieback phenomenon. We found that slower-growing trees or trees with smaller crowns already before the arrival of the fungus were more susceptible to dieback and mortality. Defoliation directly reduced growth as well as maximum earlywood vessel size, and the positive relationship between vessel size and growth rate caused a positive feedback amplifying and accelerating crown dieback. Measured non-structural carbohydrate (NSC) concentrations in the outermost five rings did not significantly vary between healthy and weakened trees, which translate into large differences in absolute available amount of NSCs. Thus, we hypothesize that a lack of NSCs (mainly sugars) leads to lower turgor pressure and smaller earlywood vessels in the following year. This might impede efficient water transport and photosynthesis, and be responsible for stronger symptoms of dieback and higher mortality rates in smaller and slower-growing trees.

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