Multiple methods of assessing nectar foraging conditions indicate peak foraging difficulty in late season

2020 ◽  
Vol 13 (6) ◽  
pp. 532-542
Author(s):  
Mihail Garbuzov ◽  
Nicholas J. Balfour ◽  
Kyle Shackleton ◽  
Hasan Al Toufailia ◽  
Luciano Scandian ◽  
...  
2018 ◽  
Vol 10 (1) ◽  
pp. 219-234
Author(s):  
John H. Hitchcock ◽  
◽  
Anthony J. Onwuegbuzie ◽  
Shannon David ◽  
Anne-Maree Ruddy ◽  
...  

2010 ◽  
Vol 18 (3) ◽  
pp. 606-610 ◽  
Author(s):  
Wu LI ◽  
Xiao-Juan YANG ◽  
Xiang-Ru TANG ◽  
Guo-Xi LI ◽  
Guo-Wei PENG ◽  
...  

Crop Science ◽  
1980 ◽  
Vol 20 (3) ◽  
pp. 330-333 ◽  
Author(s):  
D. L. Kittock ◽  
H. Fred Arle ◽  
T. J. Henneberry ◽  
L. A. Bariola ◽  
V. T. Walhood
Keyword(s):  

2020 ◽  
Vol 22 (1) ◽  
pp. 54-57
Author(s):  
FRANCO BRUNI ◽  

The article is devoted to problems in relations between the EU and Russia. Multiple methods are considered that are aimed at solving the problem of multilateralism in current conditions. The author selected and studied specific documents on essential aspects that are devoted to this topic. Studying the arising problems requires careful consideration since, in the modern world, cooperation between global actors such as the EU and Russia cannot be ignored. Despite all the challenges faced by the parties in their fields, all difficulties are conquerable, and the article provides specific methods for its solving. The article discusses some aspects and problems that require particular attention from specialists in this field. The author concludes that strong US–EU coalition could seem more coherent with history and with the traditional East–West divide. However, the recent evolution of the US attitude towards international relations weakens the probability of such coalition and its perceived payoffs. A more or less defensive Russia–China coalition has been tried with limited results; moreover, if it were possible and probable, the two western players would change their strategy to prevent it or to contain its depth. In fact, we live in a world where many talks of a serious possibility of G2 governance, a peculiar type of coalition where the US and China keep hostile and nationalistic attitudes but join forces to set the global stage in their favor, pursuing a qualitatively limited but quantitatively rich payoff. In such world, as a counterpart of this payoff, both the divided Europe and the economically much smaller Russia would lose power and suffer several kinds of economic disadvantages. Therefore, Greater Europe would be good for Russia and for the EU as well.


2017 ◽  
Vol 37 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Sanaz Aghazadeh ◽  
Marietta Peytcheva

SUMMARY We conduct a post-implementation research analysis of AS4, a standard guiding voluntary audits of material weakness (MW) remediation disclosures, to understand the reasons for the scarcity of AS4 audits in practice. We use multiple methods (experiments, comment letter analysis, and surveys) to understand the perspectives of key stakeholders. We find that regulators' expectations of the use of the standard did not come to fruition because an equilibrium market for active use of the standard could not be achieved; that managers desire to engage in AS4 audits for the riskier MWs but do not expect the associated costs to be high; and that auditors are reluctant to audit riskier MWs and would charge a considerable risk premium. Finally, we find that investors value AS4 audits, especially for riskier MWs, and find value in an AS4 audit for those risky MWs beyond that of the year-end audit. The overall findings of our study indicate that a mismatch in the cost-benefit functions of the key stakeholders led to a lack of AS4 audits. Our findings are important given the high costs associated with auditing standards development and approval.


2021 ◽  
Author(s):  
Joanna L Woods ◽  
Anne E Iskra ◽  
David H Gent

Abstract Twospotted spider mite (Tetranychus urticae Koch) is a cosmopolitan pest of numerous plants, including hop (Humulus lupulus L.). The most costly damage from the pest on hop results from infestation of cones, which are the harvested product, which can render crops unsalable if cones become discolored. We analyzed 14 yr of historical data from 312 individual experimental plots in western Oregon to identify risk factors associated with visual damage to hop cones from T. urticae. Logistic regression models were fit to estimate the probability of cone damage. The most predictive model was based on T. urticae-days during mid-July to harvest, which correctly predicted occurrence and nonoccurrence of cone damage in 91 and 93% of data sets, respectively, based on Youden’s index. A second model based on the ratio of T. urticae to predatory arthropods late in the season correctly predicted cone damage in 92% of data sets and nonoccurrence of damage in 77% of data sets. The model based on T. urticae abundance performed similarly when validated in 23 commercial hop yards, whereas the model based on the predator:prey ratio was relatively conservative and yielded false-positive predictions in 11 of the 23 yards. Antecedents of these risk factors were explored and quantified by structural equation modeling. A simple path diagram was constructed that conceptualizes T. urticae invasion of hop cones as dependent on prior density of the pest on leaves in early spring and summer, which in turn influences the development of predatory arthropods that mediate late-season density of the pest. In summary, the biological insights and models developed here provide guidance to pest managers on the likelihood of visual cone damage from T. urticae that can inform late-season management based on both abundance of the pest and its important predators. This is critically important because a formal economic threshold for T. urticae on hop does not exist and current management efforts may be mistimed to influence the pest when crop damage is most probable. More broadly, this research suggests that current management practices that target T. urticae early in the season may in fact predispose yards to later outbreaks of the pest.


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