scholarly journals Testing the multiple stressor hypothesis: chlorothalonil exposure alters transmission potential of a bumblebee pathogen but not individual host health

2021 ◽  
Vol 288 (1947) ◽  
Author(s):  
Austin C. Calhoun ◽  
Audrey E. Harrod ◽  
Toby A. Bassingthwaite ◽  
Ben M. Sadd
Keyword(s):  
Positive Association ◽  
Interactive Effects ◽  
Negative Effects ◽  
Pollination Services ◽  
Transmission Potential ◽  
Multiple Stressor ◽  
Pathogen Dynamics ◽  
Nosema Bombi ◽  
Individual Host ◽  
Host Health

Numerous threats are putting pollinator health and essential ecosystem pollination services in jeopardy. Although individual threats are widely studied, their co-occurrence may exacerbate negative effects, as posited by the multiple stressor hypothesis. A prominent branch of this hypothesis concerns pesticide–pathogen co-exposure. A landscape analysis demonstrated a positive association between local chlorothalonil fungicide use and microsporidian pathogen ( Nosema bombi ) prevalence in declining bumblebee species ( Bombus spp.), suggesting an interaction deserving further investigation. We tested the multiple stressor hypothesis with field-realistic chlorothalonil and N. bombi exposures in worker-produced B. impatiens microcolonies. Chlorothalonil was not avoided in preference assays, setting the stage for pesticide–pathogen co-exposure. However, contrary to the multiple stressor hypothesis, co-exposure did not affect survival. Bees showed surprising tolerance to Nosema infection, which was also unaffected by chlorothalonil exposure. However, previously fungicide-exposed infected bees carried more transmission-ready spores. Our use of a non-declining bumblebee and potential higher chlorothalonil exposures under some scenarios could mean stronger individual or interactive effects in certain field settings. Yet, our results alone suggest consequences of pesticide co-exposure for pathogen dynamics in host communities. This underlies the importance of considering both within- and between-host processes when addressing the multiple stressor hypothesis in relation to pathogens.

Parental breeding age effects on descendants’ longevity interact over two generations in matrilines and patrilines

2019 ◽  
Author(s):  
Zac Wylde ◽  
Foteini Spagopoulou ◽  
Amy K Hooper ◽  
Alexei A Maklakov ◽  
Russell Bonduriansky
Keyword(s):  
Maternal Age ◽  
First Generation ◽  
Age Effects ◽  
Population Variation ◽  
Paternal Age ◽  
Interactive Effects ◽  
Competitive Environment ◽  
Larval Diet ◽  
Negative Effects ◽  
Two Generations

Individuals within populations vary enormously in mortality risk and longevity, but the causes of this variation remain poorly understood. A potentially important and phylogenetically widespread source of such variation is maternal age at breeding, which typically has negative effects on offspring longevity. Here, we show that paternal age can affect offspring longevity as strongly as maternal age does, and that breeding age effects can interact over two generations in both matrilines and patrilines. We manipulated maternal and paternal ages at breeding over two generations in the neriid fly Telostylinus angusticollis. To determine whether breeding age effects can be modulated by the environment, we also manipulated larval diet and male competitive environment in the first generation. We found separate and interactive effects of parental and grandparental ages at breeding on descendants’ mortality rate and lifespan in both matrilines and patrilines. These breeding age effects were not modulated by grandparental larval diet quality or competitive environment. Our findings suggest that variation in maternal and paternal ages at breeding could contribute substantially to intra-population variation in mortality and longevity.

scholarly journals The Combined Effects of Financial Derivatives and Discretionary Accruals on the Value Relevance of Earnings and the Book Value of Equity

2015 ◽  
Vol 17 (2) ◽  
pp. 179 ◽  
Author(s):  
Etty Murwaningsari ◽  
Sidharta Utama ◽  
Hilda Rossieta
Keyword(s):  
Value Relevance ◽  
Positive Association ◽  
Wald Test ◽  
Discretionary Accruals ◽  
Financial Derivatives ◽  
Combined Effects ◽  
Price Model ◽  
Negative Effects ◽  
Book Value ◽  
Sfas 133

This study aimed to understand (1) the association between the use of discretionary accruals and financial derivatives, taking into consideration the implementation of revised PSAK 55 (1999), which was adopted from SFAS 133; (2) the combined effects of derivatives and discretionary accruals on the value relevance of earnings and equity. The analysis used panel data regressions and the Wald test over the period from 2001-2008. The results showed a positive or complementary association between derivatives and discretionary accruals. The positive association implied that managers tended to intensify the use of discretionary accruals to offset a higher use of derivatives. Price and return models demonstrated negative significant effects of derivatives on the value relevance of earnings. The return model showed negative significant effects of discretionary accruals on the value relevance of earnings but negative effects on the value relevance of equity with the price model.

scholarly journals Biochar addition alleviate the negative effects of drought and salinity stress on soybean productivity and water use efficiency

2020 ◽  
Author(s):  
Yaojun Zhang ◽  
Jiaqi Ding ◽  
Hong Wang ◽  
Lei Su ◽  
Cancan Zhao
Keyword(s):  
Grain Yield ◽  
Water Use Efficiency ◽  
Water Use ◽  
Salinity Stress ◽  
Crop Growth ◽  
Interactive Effects ◽  
Gaseous Exchange ◽  
Negative Effects ◽  
Use Efficiency ◽  
Effects Of Drought

Abstract Background: Environmental stress is a crucial factor restricting plant growth as well as crop productivity, thus influencing the agricultural sustainability. Biochar addition is proposed as an effective management to improve crop performance. However, there were few studies focused on the effect of biochar addition on crop growth and productivity under interactive effect of abiotic stress (e.g., drought and salinity). This study was conducted with a pot experiment to investigate the interaction effects of drought and salinity stress on soybean yield, leaf gaseous exchange and water use efficiency (WUE) under biochar addition. Results: Drought and salinity stress significantly depressed soybean phenology (e.g. flowering time) and all the leaf gas exchange parameters, but had inconsistent effects on soybean root growth and WUE at leaf and yield levels. Salinity stress significantly decreased photosynthetic rate, stomatal conductance, intercellular CO2 concentration and transpiration rate by 20.7%, 26.3%, 10.5% and 27.2%, respectively. Lower biomass production and grain yield were probably due to the restrained photosynthesis under drought and salinity stress. Biochar addition significantly enhanced soybean grain yield by 3.1-14.8%. Drought stress and biochar addition significantly increased WUE-yield by 27.5% and 15.6%, respectively, while salinity stress significantly decreased WUE-yield by 24.2%. Drought and salinity stress showed some negative interactions on soybean productivity and leaf gaseous exchange. But biochar addition alleviate the negative effects on soybean productivity and water use efficiency under drought and salinity stress. Conclusions: The results of the present study indicated that drought and salinity stress could significantly depress soybean growth and productivity. There exist interactive effects of drought and salinity stress on soybean productivity and water use efficiency, while we could employ biochar to alleviate the negative effects. We should consider the interactive effects of different abiotic restriction factors on crop growth thus for sustainable agriculture in the future.

scholarly journals Interactive Effects of Moss-Dominated Crusts andArtemisia ordosicaon Wind Erosion and Soil Moisture in Mu Us Sandland, China

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Yongsheng Yang ◽  
Chongfeng Bu ◽  
Xingmin Mu ◽  
Hongbo Shao ◽  
Kankan Zhang
Keyword(s):  
Soil Moisture ◽  
Wind Erosion ◽  
Water Environment ◽  
Interactive Effects ◽  
Vegetative Cover ◽  
Artemisia Ordosica ◽  
Negative Effects ◽  
Rainwater Infiltration ◽  
Bare Sand ◽  
Soil Crusts

To better understand the effects of biological soil crusts (BSCs) on soil moisture and wind erosion and study the necessity and feasibility of disturbance of BSCs in the Mu Us sandland, the effects of four treatments, including moss-dominated crusts alone,Artemisia ordosicaalone, bare sand, andArtemisia ordosicacombined with moss-dominated crusts, on rainwater infiltration, soil moisture, and annual wind erosion were observed. The major results are as follows. (1) The development of moss-dominated crusts exacerbated soil moisture consumption and had negative effects on soil moisture in the Mu Us sandland. (2) Moss-dominated crusts significantly increased soil resistance to wind erosion, and when combined withArtemisia ordosica, this effect became more significant. The contribution of moss-dominated crusts underArtemisia ordosicawas significantly lower than that of moss-dominated crusts alone in sites where vegetative coverage > 50%. (3) Finally, an appropriate disturbance of moss-dominated crusts in the rainy season in sites with high vegetative coverage improved soil water environment and vegetation succession, but disturbance in sites with little or no vegetative cover should be prohibited to avoid the exacerbation of wind erosion.

Evaluating vitamin D with graded levels of strontium supplementation on broiler chicken performance and mineral composition

2016 ◽  
Vol 56 (1) ◽  
pp. 70
Author(s):  
L. C. Browning ◽  
A. J. Cowieson
Keyword(s):  
Vitamin D ◽  
Broiler Chickens ◽  
Broiler Chicken ◽  
Bodyweight Gain ◽  
Interactive Effects ◽  
Negative Effects ◽  
Bone Composition ◽  
Tibia Bone ◽  
Commercial Broiler ◽  
Four Levels

In order to examine the interactive effects of strontium and cholecalciferol in broiler nutrition a total of 288 male broiler chickens were fed over 28 days, eight different diets with six replicates comprising of two levels of vitamin D (5000 and 10 000 IU/kg) and four levels of strontium (0, 400, 800 and 1200 mg/kg) provided as strontium carbonate. Vitamin D and strontium produced a significant interaction on growth and feed efficiency with the addition of higher levels of vitamin D ameliorating the negative effects of strontium at 1200 mg/kg. The higher level of vitamin D also improved bodyweight gain (P < 0.05), had no effect on tibia bone composition but reduced calcium, phosphorus, potassium and magnesium retention (P < 0.05). Strontium supplementation produced no advantage to chicken performance but changed tibia bone composition. It was found that calcium and sodium maintained a ratio of ~30 : 1 in tibia bone. Vitamin D and strontium produced a significant physiological interaction and further research is required to elucidate optimum levels of supplementation for commercial broiler chicken production.

SOX 404(b) exemption effects on auditor changes

2016 ◽  
Vol 31 (4/5) ◽  
pp. 387-402 ◽  
Author(s):  
Benjamin W. Hoffman ◽  
Albert L. Nagy
Keyword(s):  
Positive Association ◽  
Negative Effects ◽  
Significant Positive Association ◽  
Public Companies ◽  
Content Type ◽  
Sarbanes Oxley ◽  
Sensitivity Tests ◽  
Prior Literature ◽  
Pros And Cons ◽  
Practical Implications

Purpose This paper aims to investigate whether the Sarbanes-Oxley Act: Section 404(b) exemption caused an increase in auditor changes due to changes in expectations for both auditors and their clients. Design/methodology/approach This paper predicts that this exemption caused a significant amount of auditor changes post-exemption, due to a change in expected future economic rents (audit scope demands) for auditors (clients). Logistic regression analysis is used to examine whether auditor changes increased for non-accelerated filers (public companies with less than $75 million in public float), who were affected by this exemption, compared to auditor changes for accelerated filers (public companies with greater than $75 million in public float), who were not affected by this exemption. Findings The results show a significant positive association between the exemption and auditor dismissals for non-accelerated filers compared to that of accelerated filers. This finding is robust when sensitivity tests are used. Practical implications Prior literature finds that an increase in auditor changes can have various positive and negative effects on the affected companies. Thus, investors will be interested in the results of this paper when making their investment decisions with regard to non-accelerated filers. Social implications The results of this paper will aid policymakers as they consider the pros and cons of this exemption, as it pertains to the affected companies. Originality/value This paper is the first to study the effects of this exemption on auditor turnover for the affected companies.

A time-lagged study on the moderating role of overall satisfaction in perceived politics: Job outcomes relationships

2016 ◽  
Vol 23 (3) ◽  
pp. 321-336 ◽  
Author(s):  
Farooq Ahmed Jam ◽  
Magda B L Donia ◽  
Usman Raja ◽  
Chong Hui Ling
Keyword(s):  
Job Performance ◽  
Job Stress ◽  
Interpersonal Conflict ◽  
High Stress ◽  
Interactive Effects ◽  
Negative Effects ◽  
Negative Effect ◽  
Time Lagged ◽  
Positive Effect ◽  
High Politics

AbstractIn a time-lagged study with independent measures (N=115, paired responses), we examined the interactive effects of perceived organizational politics and overall satisfaction on job stress, interpersonal conflict, job performance, and creativity. The data were collected from a diverse sample of employees from various workplaces in Pakistan. The findings showed that perceived politics had a positive effect on job stress, while overall satisfaction had a negative effect on interpersonal conflict and a positive effect on creative performance. The results also revealed that in the face of high politics, highly satisfied individuals demonstrated higher levels of creativity and job performance. However, in this context of high politics negative effects were also observed, namely that highly satisfied individuals participated in interpersonal conflict and experienced high stress.

Examining the interactive effects of accountability, politics, and voice

2014 ◽  
Vol 19 (4) ◽  
pp. 358-380 ◽  
Author(s):  
Wayne A. Hochwarter ◽  
B. Parker Ellen III ◽  
Gerald R. Ferris
Keyword(s):  
Work Performance ◽  
Interactive Effects ◽  
Negative Outcomes ◽  
Voice Behavior ◽  
Negative Effects ◽  
Content Type ◽  
Job Tension ◽  
Individual Difference Variables ◽  
Political Environments ◽  
Felt Accountability

Purpose – Research has shown accountability can produce both positive and negative outcomes. Further, because of inherent environmental uncertainty, perceptions of organizational politics often interact with accountability to produce negative effects. However, using uncertainty management theory, the purpose of this paper is to argue that employees can use proactive voice to exercise control in the ambiguity of highly accountable and political environments. Design/methodology/approach – This two sample study of graduate school alumni (n=211) and insurance employees (n=186) explored the three-way interaction of felt accountability×politics perceptions×proactive voice on work performance, job satisfaction, and job tension. Findings – As hypothesized, high levels of felt accountability and politics were most strongly associated with favorable outcomes when coupled with increased voice behavior. Conversely, felt accountability and politics were related to negative outcomes in settings associated with low proactive voice. Results supported in Sample 1 were then constructively replicated in Sample 2. Practical implications – All employees are held accountable to some degree, and all work in potentially political settings. Often, these environmental features are dictated to employees, leaving only employee reactions in direct control. One possible response is voice. As demonstrated in the present research, employees who engage in proactive voice appear to exercise some degree of control over their environment, resulting in more positive outcomes than their less active counterparts. Originality/value – The present research extends understanding regarding the effects of accountability in organizations by demonstrating that contextual factors (e.g. politics) and individual difference variables (e.g. in levels of proactive voice) differentiate favorable vs unfavorable outcomes of accountability.

scholarly journals The dynamics of food chains under climate change and nutrient enrichment

2012 ◽  
Vol 367 (1605) ◽  
pp. 2935-2944 ◽  
Author(s):  
Amrei Binzer ◽  
Christian Guill ◽  
Ulrich Brose ◽  
Björn C. Rall
Keyword(s):  
Food Chain ◽  
Nutrient Enrichment ◽  
Biodiversity Loss ◽  
Low Fertility ◽  
Interactive Effects ◽  
Large Species ◽  
Negative Effects ◽  
Food Web Structure ◽  
Population Dynamic Model ◽  
The Individual

Warming has profound effects on biological rates such as metabolism, growth, feeding and death of organisms, eventually affecting their ability to survive. Using a nonlinear bioenergetic population-dynamic model that accounts for temperature and body-mass dependencies of biological rates, we analysed the individual and interactive effects of increasing temperature and nutrient enrichment on the dynamics of a three-species food chain. At low temperatures, warming counteracts the destabilizing effects of enrichment by both bottom-up (via the carrying capacity) and top-down (via biological rates) mechanisms. Together with increasing consumer body masses, warming increases the system tolerance to fertilization. Simultaneously, warming increases the risk of starvation for large species in low-fertility systems. This effect can be counteracted by increased fertilization. In combination, therefore, two main drivers of global change and biodiversity loss can have positive and negative effects on food chain stability. Our model incorporates the most recent empirical data and may thus be used as the basis for more complex forecasting models incorporating food-web structure.

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