scholarly journals Development and Assessment of Ash Mortality Models in Relation to Emerald Ash Borer Infestation

2015 ◽  
Vol 41 (5) ◽  
Author(s):  
Rachel Clark ◽  
Kayla Boyes ◽  
Lori Morgan ◽  
Andrew Storer ◽  
Jordan Marshall

Emerald ash borer is a pest of North American ash that has caused significant mortality within its introduced range. The timeline for tree mortality, once infested by emerald ash borer, is variable for individual trees, with a small proportion surviving infestation. Using tree health assessments and signs of emerald ash borer infestation, researchers developed decision models to predict the probability of mortality. Two resulting models performed well at correctly predicting mortality (>83% correct) and significantly separating probability of mortality for those trees. Both models used diameter at breast height (DBH) and presence of bark splits, with one including percent crown dieback and the other including vigor rating (overall tree health assessment). A third model had reduced correct prediction of mortality, but was still potentially an effective model. Other tested models had shortcomings in prediction of mortality or in separation of probabilities of mortality. Using variables from three potential decision models, the year of mortality was modeled. However, specific year prediction was not as effective. Because of a wide range of external factors, prediction of a specific year of mortality may not be appropriate. Using DBH and rapid health and infestation assessment data, the authors were able to correctly predict ash mortality within a three-year period for the majority of trees within this study. Management strategies that use these models for developing hierarchical removal programs for infested ash may distribute financial and environmental costs over multiple years as opposed to mass removal of street and park trees.

2019 ◽  
Vol 64 (1) ◽  
pp. 51-71 ◽  
Author(s):  
Philip J. Lester ◽  
Jacqueline R. Beggs

Three species of Vespula have become invasive in Australia, Hawai‘i, New Zealand, and North and South America and continue to spread. These social wasp species can achieve high nest densities, and their behavioral plasticity has led to substantial impacts on recipient communities. Ecologically, they affect all trophic levels, restructuring communities and altering resource flows. Economically, their main negative effect is associated with pollination and the apicultural industry. Climate change is likely to exacerbate their impacts in many regions. Introduced Vespula spp. likely experience some degree of enemy release from predators or parasites, although they are exposed to a wide range of microbial pathogens in both their native and introduced range. Toxic baits have been significantly improved over the last decade, enabling effective landscape-level control. Although investigated extensively, no effective biological control agents have yet been found. Emerging technologies such as gene drives are under consideration.


2015 ◽  
Vol 25 (1) ◽  
pp. 15-23 ◽  
Author(s):  
Ryan W. McCreery ◽  
Elizabeth A. Walker ◽  
Meredith Spratford

The effectiveness of amplification for infants and children can be mediated by how much the child uses the device. Existing research suggests that establishing hearing aid use can be challenging. A wide range of factors can influence hearing aid use in children, including the child's age, degree of hearing loss, and socioeconomic status. Audiological interventions, including using validated prescriptive approaches and verification, performing on-going training and orientation, and communicating with caregivers about hearing aid use can also increase hearing aid use by infants and children. Case examples are used to highlight the factors that influence hearing aid use. Potential management strategies and future research needs are also discussed.


2021 ◽  
Vol 9 (4) ◽  
pp. 862
Author(s):  
Vittoria Catara ◽  
Jaime Cubero ◽  
Joël F. Pothier ◽  
Eran Bosis ◽  
Claude Bragard ◽  
...  

Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.


2021 ◽  
Author(s):  
Jordan Kern ◽  
Nathalie Voisin ◽  
Sean Turner ◽  
Hongxiang Yan ◽  
Konstantinos Oikonomou

<p>Given the wide range of institutional and market contexts in which hydroelectric dams are operated, determining the value added from improvements in hydrologic forecasts is a challenge. Many previous examples of hydrologic forecasts being used to optimize hydropower production strategies at dams focus on a single reservoir system or watershed, with a key assumption that the marginal value of hydropower production is exogenously-defined (dams are ‘price takers’ in markets for electricity that exhibit no market power). In some cases, this may accurately reflect current institutional boundaries and decision making processes. However, with increased attention being paid to how more coordinated grid management strategies, including management of hydropower assets, could facilitate deep integration of renewable energy, it is critical to understand how the use of improved hydrologic forecasts could produce wider grid-scale benefits, including  lower costs and emissions. In this study, we quantify the value of streamflow forecasts to a centralized power system operator in charge of coordinating sub-weekly operations of hydropower assets, using the Western U.S. as a case study. We propagate flow forecasts through realistic models of reservoir operations and models of bulk power systems/wholesale electricity markets. Our results shed light on how the value of flow forecasts to grid operations can vary across regions and power systems. They also highlight the potential for conflicts between firm-specific objectives (profit maximization) and system-wide objectives (minimization of costs and emissions) when determining value added from hydrologic forecasts.  </p>


2018 ◽  
Vol 76 (4) ◽  
pp. 1122-1130 ◽  
Author(s):  
Lotta Clara Kluger ◽  
Sophia Kochalski ◽  
Arturo Aguirre-Velarde ◽  
Ivonne Vivar ◽  
Matthias Wolff

Abstract In February and March 2017, a coastal El Niño caused extraordinary heavy rains and a rise in water temperatures along the coast of northern Peru. In this work, we document the impacts of this phenomenon on the artisanal fisheries and the scallop aquaculture sector, both of which represent important socio-economic activities for the province of Sechura. Despite the perceived absence of effective disaster management and rehabilitation policies, resource users opted for a wide range of different adaptation strategies and are currently striving towards recovery. One year after the event, the artisanal fisheries fleet has returned to operating almost on a normal scale, while the aquaculture sector is still drastically impacted, with many people continuing to work in different economic sectors and even in other regions of the country. Recovery of the social-ecological system of Sechura likely depends on the occurrence of scallop seed and the financial capacity of small-scale producers to reinitiate scallop cultures. Long-term consequences of this coastal El Niño are yet to be studied, though the need to develop trans-local and trans-sectoral management strategies for coping with disturbance events of this scale is emphasized.


Weed Science ◽  
2018 ◽  
Vol 67 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Nadeem Iqbal ◽  
Sudheesh Manalil ◽  
Bhagirath S. Chauhan ◽  
Steve W. Adkins

AbstractSesbania [Sesbania cannabina(Retz.) Pers.] is a problematic emerging weed species in Australian cotton-farming systems. However, globally, no information is available regarding its seed germination biology, and better understanding will help in devising superior management strategies to prevent further infestations. Laboratory and glasshouse studies were conducted to evaluate the impact of various environmental factors such as light, temperature, salt, osmotic and pH stress, and burial depth on germination and emergence of two Australian biotypes ofS. cannabina. Freshly harvested seeds of both biotypes possessed physical dormancy. A boiling-water scarification treatment (100±2 C) of 5-min duration was the optimum treatment to overcome this dormancy. Once dormancy was broken, the Dalby biotype exhibited a greater germination (93%) compared with the St George biotype (87%). The nondormant seeds of both biotypes showed a neutral photoblastic response to light and dark conditions, with germination marginally improved (6%) under illumination. Maximum germination of both biotypes occurred under an alternating temperature regime of 30/20 and 35/25 C and under constant temperatures of 32 or 35 C, with no germination at 8 or 11 C. Seed germination of both biotypes decreased linearly from 87% to 14% with an increase in moisture stress from 0.0 to −0.8 MPa, with no germination possible at −1.0 MPa. There was a gradual decline in germination for both biotypes when imbibed in a range of salt solutions of 25 to 250 mM, with a 50% reduction in germination occurring at 150 mM. Both biotypes germinated well under a wide range of pH values (4.0 to 10.0), with maximum germination (94%) at pH 9.0. The greatest emergence rate of the Dalby (87%) and St George (78%) biotypes was recorded at a burial depth of 1.0 cm, with no emergence at 16.0 cm. Deep tillage seems to be the best management strategy to stopS. cannabina’s emergence and further infestation of cotton (Gossypium hirsutumL.) fields. The findings of this study will be helpful to cotton agronomists in devising effective, sustainable, and efficient integrated weed management strategies for the control ofS. cannabinain cotton cropping lands.


2020 ◽  
Vol 197 ◽  
pp. 01004
Author(s):  
Martina Capone ◽  
Elisa Guelpa ◽  
Vittorio Verda

As District Heating (DH) networks are experiencing an evolution towards the so-called 4th generation, there is a need to update the currently used models to take into account the ever-increasing complexity of this technology. Indeed, to further improve the reduction in energy consumption and carbon-dioxide emissions, a wide range of technologies and management strategies are being introduced within district heating, such as a large exploitation of Renewable Energy Sources (RES). As a consequence, thermal transients assume a major importance, posing the need to redefine the relevant physical parameters and to develop a model which accurately describes their behaviour. In this framework, this paper proposes a quantitative analysis of the influence of the pipe heat-capacity on the model. Moreover, an equivalent-model, which is able to take into account the two heat capacities of steel and water in just one equation, is proposed and compared with two commonly used approaches. One of the features of the proposed model is the suitability for application to large networks. To prove its capabilities, an application to the Turin district heating network, which is among the largest systems in Europe, is proposed. Results show significant improvements in terms of accuracy over computational time ratio.


2020 ◽  
Vol 7 (3) ◽  
pp. 57-66
Author(s):  
J Shifa Fathima

The Indian Banking industry is seeing an exceptional challenge. To remain ahead, banks are thinking of plenty of services to draw customers. Services including 24-hours banking, Service at entryway step, Telephone banking, Internet banking, Extended Business Hours (EBH), Speedy handling are just a couple to mention. The larger piece of the present bank transactions happens elsewhere other than in-branch premises. This shows the growth of “virtual” banks in India. With accommodation, speed, productivity, and adequacy, these virtual banks, as a result, have opened up another universe of conceivable outcomes and brought major changes in giving a wide scope of services. Virtual banks are presently observed as a response to the challenge of planning another service channel that is completely secure, useful, and which customers can promptly figure out how to utilize and confide in it. (Aladwani, A, M.) Virtual banking, an amazing “esteem included” instrument, has become the point of convergence for banks to attract and hold customers. However, the point of these services is to satisfy customers; there is a need to comprehend customer mindfulness, observation, and significantly the degree of satisfaction. Virtual banking is a transporter that licenses customers to access and do economic transactions on their financial foundation obligations from their web empowered PC systems with net association with banks’ web locales whenever 24 Hours. Banks assume a vital job in advancing online businesses. Even though V-customers have the alternative of money down, which is by all accounts secure reliable, still there is an inclination for the V-payment plans, which must be given through banks. Banks go about as solid and dependable go-betweens in online transactions, and they give an intense opening in the online business. At present, banks have V-payment systems like Internet banking, electronic fund transfers (NEFT/RTGS), plastic money (credit card and debit card), and portable banking. These systems give payment to online transactions like the online acquisition of items, versatile revives, lodging booking, ticket booking, and so forth by considering a wide range of safety efforts. For the genuine working of these V-services, the need for able frameworks is an unavoidable element. Reserve Bank of India is observing and inspecting the legitimate and different requirements of V-Banking on persistent bases to guarantee that V-banking would create on sound lines, and V-Banking related challenges would not represent a risk to financial dependability. Hence, the present study is on the challenges of Virtual banking services in its challenge management strategies and the study based on secondary sources of data.


2021 ◽  
Author(s):  
Michael Bradshaw ◽  
Holly Packard Bartholomew ◽  
Dylan Hendricks ◽  
Autumn Maust ◽  
Wayne Jurick II

Fungicides are the primary tools to control a wide range of postharvest fungal pathogens. Fungicide resistance is a widespread problem that has reduced fungicide efficacy. Resistance to FRAC 1 chemistries are associated with mutations in amino acid position 198 in the β-tubulin gene. In the current study we conducted a meta-analysis of β-tubulin sequences to infer temporal, spatial, plant host and pathogen genus patterns of fungicide resistance in postharvest fungal pathogens. In total, data was acquired from 2647 specimens from 12 genera of fungal phytopathogens residing in 53 countries, on over 200 hosts collected between 1926-2020. The specimens containing a position 198 mutation were globally distributed in a variety of pathosystems. Analyses showed that there is an association between the mutation and the year an isolate was collected, the pathogen genus, the pathogen host and the collection region. Interestingly, fungicide resistant β-tubulin genotypes have been in a decline since their peak between 2005-2009. FRAC 1 fungicide usage data followed a similar pattern in that applications have been in a decline since their peak between 1997 and 2003. The data shows that, with the reduction of selection pressure, FRAC 1 fungicide resistance in fungal populations will decline within 5-10 years. Based on this line of evidence, we contend that a β-tubulin position 198 mutation has uncharacterized fitness cost(s) on fungi in nature. The compiled dataset can inform end users on the regions and hosts that are most prone to contain resistant pathogens and assist decisions concerning fungicide resistant management strategies.


Viruses ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2275
Author(s):  
Yanxi Liu ◽  
Mengjiao Liu ◽  
Ran Hu ◽  
Jun Bai ◽  
Xiaoqing He ◽  
...  

Bacteriophages are viruses that specifically infect target bacteria. Recently, bacteriophages have been considered potential biological control agents for bacterial pathogens due to their host specificity. Pseudomonas syringae pv. actinidiae (Psa) is a reemerging pathogen that causes bacterial canker of kiwifruit (Actinidia sp.). The economic impact of this pest and the development of resistance to antibiotics and copper sprays in Psa and other pathovars have led to investigation of alternative management strategies. Phage therapy may be a useful alternative to conventional treatments for controlling Psa infections. Although the efficacy of bacteriophage φ6 was evaluated for the control of Psa, the characteristics of other DNA bacteriophages infecting Psa remain unclear. In this study, the PHB09 lytic bacteriophage specific to Psa was isolated from kiwifruit orchard soil. Extensive host range testing using Psa isolated from kiwifruit orchards and other Pseudomonas strains showed PHB09 has a narrow host range. It remained stable over a wide range of temperatures (4–50 °C) and pH values (pH 3–11) and maintained stability for 50 min under ultraviolet irradiation. Complete genome sequence analysis indicated PHB09 might belong to a new myovirus genus in Caudoviricetes. Its genome contains a total of 94,844 bp and 186 predicted genes associated with phage structure, packaging, host lysis, DNA manipulation, transcription, and additional functions. The isolation and identification of PHB09 enrich the research on Pseudomonas phages and provide a promising biocontrol agent against kiwifruit bacterial canker.


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