Long-term effects of an insecticide on a stored-wheat ecosystem

1986 ◽  
Vol 64 (11) ◽  
pp. 2558-2569 ◽  
Author(s):  
N. D. G. White ◽  
R. N. Sinha ◽  
J. T. Mills

Two granaries near Winnipeg, each containing 141 of dry wheat, were filled in September 1982 and the impact of a contact insecticide on the ecosystem was determined monthly for 27 months. The wheat in one granary was treated with malathion prior to storage and the wheat in the other was left untreated. Variables monitored throughout each bulk included: introduced insect and naturally occurring mite numbers, seed germination, seed-borne mycoflora, insecticide residue levels, and seed temperature and moisture. There were significant differences (P < 0.01) in most variables within granaries between samples from the top of the grain bulk and 1-m depth. Multivariate analysis of variance indicated significantly more (P < 0.01) arthropods and more seed infection by the fungus Penicillium in the control granary. Principal component analysis of data from each granary on each sampling date indicated the first components, which accounted for most of the variation in the systems, mainly involved temperature, moisture, fungi, and insecticide (when present); the second components involved fungi; and the third components involved fungi and arthropods, even in the treated ecosystem. The presence of a contact insecticide in a stored-wheat ecosystem had significant effects on the faunal community and definite but less conspicuous effects on the mycofloral community.

2005 ◽  
Vol 10 (1) ◽  
pp. 33-50 ◽  
Author(s):  
Dean Pruitt

AbstractField experiments, in which the researcher manipulates one or more variables in a naturally occurring setting, have sometimes been used in studies of social conflict and should probably be used more often. They are more useful than observational studies for assessing the impact of novel conditions, establishing cause and effect, and reducing confounding. And they are more useful than laboratory experiments for examining long-term effects and those that involve strong passions, and for establishing external validity. However field experiments also have their limitations. Some variables cannot be practically or ethically manipulated and require the use of observational methods, which are also more useful for looking at the relationships among a large number of variables and for estimating the strength of association between variables. Furthermore, laboratory experiments allow more control of conditions and greater flexibility in designing manipulations. What this suggests is that all three methods have their value.


Psibernetika ◽  
2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Devina Calista ◽  
Garvin Garvin

<p><em>Child abuse by parents is common in households. The impact of violence on children will bring short-term effects and long-term effects that can be attributed to their various emotional, behavioral and social problems in the future; especially in late adolescence that will enter adulthood. Resilience factors increase the likelihood that adolescents who are victims of childhood violence recover from their past experiences</em><em>,</em><em> become more powerful individuals and have a better life. The purpose of this study was to determine the source of resilience in late adolescents who experienced violence from parents in their childhood. This research uses qualitative research methods with in-depth interviews as a method of data collection. The result shows that the three research participants have the aspects of "I Have", "I Am", and "I Can"; a participant has "I Can" aspects as a source of resilience, and one other subject has no source of resilience. The study concluded that parental affection and acceptance of the past experience have role to the three sources of resilience (I Have, I Am, and I Can)</em></p><p><em> </em></p><p><strong><em>Keyword : </em></strong><em>Resilience, adolescence, violence, parents</em></p>


Author(s):  
Balázs Égert ◽  
Peter Gal

This chapter describes and discusses a new supply-side framework that quantifies the impact of structural reforms on per capita income in OECD countries. It presents the overall macroeconomic impacts of reforms by aggregating over the effects on physical capital, employment, and productivity through a production function. On the basis of reforms defined as observed changes in policies, the chapter finds that product market regulation has the largest overall single policy impact five years after the reforms. But the combined impact of all labour market policies is considerably larger than that of product market regulation. The paper also shows that policy impacts can differ at different horizons. The overall long-term effects on GDP per capita of policies transiting through capital deepening can be considerably larger than the five- to ten-year impacts. By contrast, the long-term impact of policies coming only via the employment rate channel materializes at a shorter horizon.


Author(s):  
Sofia Ainonen ◽  
Mysore V Tejesvi ◽  
Md. Rayhan Mahmud ◽  
Niko Paalanne ◽  
Tytti Pokka ◽  
...  

Abstract Background Intrapartum antibiotic prophylaxis (IAP) is widely used, but the evidence of the long-term effects on the gut microbiota and subsequent health of children is limited. Here, we compared the impacts of perinatal antibiotic exposure and later courses of antibiotic courses on gut microbiota. Methods This was a prospective, controlled cohort study among 100 vaginally delivered infants with different perinatal antibiotic exposures: control (27), IAP (27), postnatal antibiotics (24), and IAP and postnatal antibiotics (22). At 1 year of age, we performed next-generation sequencing of the bacterial 16S ribosomal RNA gene of fecal samples. Results Exposure to the perinatal antibiotics had a clear impact on the gut microbiota. The abundance of the Bacteroidetes phylum was significantly higher in the control group, whereas the relative abundance of Escherichia coli was significantly lower in the control group. The impact of the perinatal antibiotics on the gut microbiota composition was greater than exposure to later courses of antibiotics (28% of participants). Conclusions Perinatal antibiotic exposure had a marked impact on the gut microbiota at the age of 1 year. The timing of the antibiotic exposure appears to be the critical factor for the changes observed in the gut microbiota. Impact Infants are commonly exposed to IAP and postnatal antibiotics, and later to courses of antibiotics during the first year of life. Perinatal antibiotics have been associated with an altered gut microbiota during the first months of life, whereas the evidence regarding the long-term impact is more limited. Perinatal antibiotic exposure had a marked impact on the infant’s gut microbiota at 1 year of age. Impact of the perinatal antibiotics on the gut microbiota composition was greater than that of the later courses of antibiotics at the age of 1 year.


Author(s):  
Leo Sher

Abstract Parental alienation is defined as a mental state in which a child, usually one whose parents are engaged in a high-conflict separation or divorce, allies himself strongly with one parent (the preferred parent) and rejects a relationship with the other parent (the alienated parent) without legitimate justification. Parental alienation may affect men’s mental health: a) parental alienation negatively influences mental health of male children and adolescents who are victims of parental alienation. Alienated children/adolescents display guilt, sadness, and depressed mood; low self-esteem and lack of self-confidence; distress and frustration; lack of impulse control, substance abuse and delinquent behavior; separation anxiety, fears and phobias; hypochondria and increased tendency to develop psychosomatic illness; suicidal ideation and suicide attempt; sleep and eating disorders; educational problems; enuresis and encopresis; b) parental alienation negatively affects the mental health of adult men who were victims of parental alienation when they were children and/or adolescents. Long-term effects of parental alienation include low self-esteem, depression, drug/alcohol abuse, lack of trust, alienation from own children, divorce, problems with identity and not having a sense of belonging or roots, choosing not to have children to avoid being rejected by them, low achievement, anger and bitterness over the time lost with the alienated parent; c) parental alienation negatively influences mental health of men who are alienated from their children. Fathers who have lost some or all contact with their children for months or years following separation or divorce may be depressed and suicidal.


2009 ◽  
Vol 5 (3) ◽  
pp. 116-118 ◽  
Author(s):  
Len Lichtenfeld

Although we have made some progress in understanding long-term effects of some cancer treatments, there is still much more to learn about the impact of our treatments on our patients.


eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Patrícia A Correia ◽  
Eran Lottem ◽  
Dhruba Banerjee ◽  
Ana S Machado ◽  
Megan R Carey ◽  
...  

Serotonin (5-HT) is associated with mood and motivation but the function of endogenous 5-HT remains controversial. Here, we studied the impact of phasic optogenetic activation of 5-HT neurons in mice over time scales from seconds to weeks. We found that activating dorsal raphe nucleus (DRN) 5-HT neurons induced a strong suppression of spontaneous locomotor behavior in the open field with rapid kinetics (onset ≤1 s). Inhibition of locomotion was independent of measures of anxiety or motor impairment and could be overcome by strong motivational drive. Repetitive place-contingent pairing of activation caused neither place preference nor aversion. However, repeated 15 min daily stimulation caused a persistent increase in spontaneous locomotion to emerge over three weeks. These results show that 5-HT transients have strong and opposing short and long-term effects on motor behavior that appear to arise from effects on the underlying factors that motivate actions.


Author(s):  
Khaled M. Hassan ◽  
Asala M. Wafa ◽  
Manea S. Alosaimi ◽  
Kawthar A. Bokari ◽  
Mosab A. Alsobhi ◽  
...  

Stroke is a major cerebrovascular disease causes high mortality and morbidity in people around the world. Stroke is the third leading cause of death and the leading cause of adult disability. The largest country in the middle East, the Kingdom of Saudi Arabia (KSA), has been occupying approximately four-fifths of the Arabian Peninsula supporting a population of more than 28 million. Stroke is getting to be a quickly expanding issue and is the leading cause of illness and deaths in Saudi Arabia. It is clear that researches and studies regarding the incidence, prevalence and their sociodemographic properties of stroke is still incomplete due to lack of present studies being conducted in these specified areas. This article aims to discuss the aspect of stroke in Saudi Arabia beside the effects of modifiable and the non-modifiable risk factors from the literature published. 


2021 ◽  
Vol 50 (1) ◽  
Author(s):  
Tamar Schlick ◽  
Stephanie Portillo-Ledesma ◽  
Christopher G. Myers ◽  
Lauren Beljak ◽  
Justin Chen ◽  
...  

We reassess progress in the field of biomolecular modeling and simulation, following up on our perspective published in 2011. By reviewing metrics for the field's productivity and providing examples of success, we underscore the productive phase of the field, whose short-term expectations were overestimated and long-term effects underestimated. Such successes include prediction of structures and mechanisms; generation of new insights into biomolecular activity; and thriving collaborations between modeling and experimentation, including experiments driven by modeling. We also discuss the impact of field exercises and web games on the field's progress. Overall, we note tremendous success by the biomolecular modeling community in utilization of computer power; improvement in force fields; and development and application of new algorithms, notably machine learning and artificial intelligence. The combined advances are enhancing the accuracy and scope of modeling and simulation, establishing an exemplary discipline where experiment and theory or simulations are full partners. Expected final online publication date for the Annual Review of Biophysics, Volume 50 is May 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


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