scholarly journals Novel parasite invasion leads to rapid demographic compensation and recovery in an experimental population of guppies

2020 ◽  
Vol 117 (36) ◽  
pp. 22580-22589
Author(s):  
Emma L.B. Rogowski ◽  
Andy D. Van Alst ◽  
Joseph Travis ◽  
David N. Reznick ◽  
Tim Coulson ◽  
...  
Keyword(s):  
Species Interactions ◽  
Poecilia Reticulata ◽  
Somatic Growth ◽  
Experimental Population ◽  
Parasite Invasion ◽  
Global Movement ◽  
Negative Effect ◽  
Camallanus Cotti ◽  
Analyze Data

The global movement of pathogens is altering populations and communities through a variety of direct and indirect ecological pathways. The direct effect of a pathogen on a host is reduced survival, which can lead to decreased population densities. However, theory also suggests that increased mortality can lead to no change or even increases in the density of the host. This paradoxical result can occur in a regulated population when the pathogen’s negative effect on survival is countered by increased reproduction at the lower density. Here, we analyze data from a long-term capture–mark–recapture experiment of Trinidadian guppies (Poecilia reticulata) that were recently infected with a nematode parasite (Camallanus cotti). By comparing the newly infected population with a control population that was not infected, we show that decreases in the density of the infected guppy population were transient. The guppy population compensated for the decreased survival by a density-dependent increase in recruitment of new individuals into the population, without any change in the underlying recruitment function. Increased recruitment was related to an increase in the somatic growth of uninfected fish. Twenty months into the new invasion, the population had fully recovered to preinvasion densities even though the prevalence of infection of fish in the population remained high (72%). These results show that density-mediated indirect effects of novel parasites can be positive, not negative, which makes it difficult to extrapolate to how pathogens will affect species interactions in communities. We discuss possible hypotheses for the rapid recovery.

Infrastructure mortgage in Russia: Opportunities and prospects

2019 ◽  
pp. 114-133
Author(s):  
G. I. Idrisov ◽  
Y. Yu. Ponomarev
Keyword(s):  
Federal Government ◽  
Public Debt ◽  
Budget Deficit ◽  
Expert Assessment ◽  
Inflation Expectations ◽  
Direct Impact ◽  
Long Run ◽  
Gdp Growth Rate ◽  
Negative Effect

The article shows that depending on the goals pursued by the federal government and the available interbudgetary tools a different design of infrastructure mortgage is preferable. Three variants of such mortgage in Russia are proposed, each of which is better suited for certain types of projects and uses different forms of subsidies. According to our expert assessment the active use of infrastructure mortgage in Russia can increase the average annual GDP growth rate by 0.5 p. p. on the horizon of 5—7 years. In the long run the growth of infrastructure financing through the use of infrastructure mortgage could increase long-term economic growth by 0.9 p. p., which in 20—30 years can add 20—30% of GDP to the economy. However, the change in the structure of budget expenditures in the absence of an increase in the budget deficit and public debt will cause no direct impact on monetary policy. The increase in the deficit and the build-up of public debt will have a negative effect on inflation expectations, which will require monetary tightening for a longer time to stabilize them.

The Transnational Women's Rights Movement and the World Economy

2020 ◽  
Vol 6 (2) ◽  
pp. 145-173 ◽  
Author(s):  
Heidi E. Rademacher
Keyword(s):  
Women's Rights ◽  
Small Body ◽  
World System ◽  
World Society ◽  
Women’S Rights ◽  
Social Movement Organizations ◽  
Global Movement ◽  
Negative Effect ◽  
Society Perspective ◽  
The Impact

Promoting the ratification of the Convention on the Elimination of All Forms of Discrimination against Women (CEDAW) was a key objective of the transnational women's movement of the 1980s and 1990s. Yet, few studies examine what factors contribute to ratification. The small body of literature on this topic comes from a world-society perspective, which suggests that CEDAW represented a global shift toward women's rights and that ratification increased as international NGOs proliferated. However, this framing fails to consider whether diffusion varies in a stratified world-system. I combine world-society and world-systems approaches, adding to the literature by examining the impact of women's and human rights transnational social movement organizations on CEDAW ratification at varied world-system positions. The findings illustrate the complex strengths and limitations of a global movement, with such organizations having a negative effect on ratification among core nations, a positive effect in the semiperiphery, and no effect among periphery nations. This suggests that the impact of mobilization was neither a universal application of global scripts nor simply representative of the broad domination of core nations, but a complex and diverse result of civil society actors embedded in a politically stratified world.

The depressing (negative) effect of oestradiol benzoate on the in vitro secretion of LH and FSH by the pituitary gland of the LRH-pretreated long-term ovariectomized rat changes into the augmentative (positive) effect after discontinuation of the LRH-pretreatment

1985 ◽  
Vol 110 (3) ◽  
pp. 329-337 ◽  
Author(s):  
G. A. Schuiling ◽  
H. Moes ◽  
T. R. Koiter
Keyword(s):  
Depressing Effect ◽  
Ovx Rats ◽  
Gonadotrophin Secretion ◽  
Oestradiol Benzoate ◽  
Negative Effect ◽  
Positive Effect ◽  
Perifusion System

Abstract. The effect of pretreatment in vivo with oestradiol benzoate on in vitro secretion of LH and FSH was studied in long-term ovariectomized (OVX) rats both at the end of a 5-day continuous in vivo pretreatment with LRH and 4-days after cessation of such LRH pretreatment. Rats were on day 0 sc implanted with osmotic minipumps which released LRH at the rate of 250 ng/h. Control rats were implanted with a piece of silicone elastomer with the dimensions of a minipump. On days 2 and 4 the rats were injected with either 3 μg EB or with oil. On day 5 part of the rats were decapitated and the in vitro autonomous (i.e. non-LRH-stimulated) and 'supra-maximally' LRHstimulated release of LH and FSH was studied using a perifusion system. From other rats the minipumps were removed on day 5 and perifusion was performed on day 9. On the 5th day of the in vivo LRH pretreatment the pituitary LH/FSH stores were partially depleted; the pituitaries of the EB-treated rats more so than those of the oil-injected rats. EB alone had no significant effect on the content of the pituitary LH- and FSH stores. On day 9, i.e. 4 days after removal of the minipumps, the pituitary LH and FSH contents had increased in both the oil- and the EB injected rats, but had not yet recovered to control values. In rats not subjected to the 5-days pretreatment with LRH EB had a positive effect on the supra-maximally LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. EB had no effect on the non-stimulated secretion of FSH. After 5 days of in vivo pretreatment with LRH only, the in vitro non-stimulated and supra-maximally LRH-stimulated secretion of both LH and FSH were strongly impaired, the effect correlating well with the LRH-induced depletion of the pituitary LH/FSH stores. In such LRH-pretreated rats EB had on day 5 a negative effect on the (already depressed) LRH-stimulated secretion of LH (not on that of FSH). EB had no effect on the non-stimulated LH/FSH secretion. It could be demonstrated that the negative effect of the combined LRH/EB pretreatment was mainly due to the depressing effect of this treatment on the pituitary LH and FSH stores: the effect of oestradiol on the pituitary LRH-responsiveness (release as related to pituitary gonadotrophin content) remained positive. In LRH-pretreated rats, however, this positive effect of EB was smaller than in rats not pretreated with LRH. Four days after removal of the minipumps there was again a positive effect of EB on the LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. The positive effect of EB on the pituitary LRH-responsiveness was as strong as in rats which had not been exposed to exogenous LRH. The non-stimulated secretion of FSH was again not affected by EB. The results demonstrate that the effect of EB on the oestrogen-sensitive components of gonadotrophin secretion consists of two components: an effect on the pituitary LRH-responsiveness proper, and an effect on the pituitary LH/FSH stores. The magnitude of the effect of EB on the LRH-responsiveness is LRH dependent: it is very weak (almost zero) in LRH-pretreated rats, but strong in rats not exposed to LRH as well as in rats of which the LRH-pretreatment was stopped 4 days previously. Similarly, the effect of EB on the pituitary LH and FSH stores is LRH-dependent: in the absence of LRH, EB has no influence on the contents of these stores, but EB can potentiate the depleting effect of LRH on the LH/FSH-stores. Also this effect disappear after cessation of the LRH-pretreatment.

Research on the Economic Organization Environmental Impact

2017 ◽  
Vol 68 (3) ◽  
pp. 599-601
Author(s):  
Dan Paul Stefanescu ◽  
Oana Roxana Chivu ◽  
Claudiu Babis ◽  
Augustin Semenescu ◽  
Alina Gligor
Keyword(s):  
Economic Activity ◽  
Economic Organization ◽  
Economic Activities ◽  
Environmental Implications ◽  
Minimal Impact ◽  
Wide Range ◽  
Material Environment ◽  
Negative Effect ◽  
Harmful Effects

Any economic activity carried out by an organization, can generate a wide range of environmental implications. Particularly important, must be considered the activities that have a significant negative effect on the environment, meaning those which pollute. Being known the harmful effects of pollution on the human health, the paper presents two models of utmost importance, one of the material environment-economy interactions balance and the other of the material flows between environmental factors and socio-economic activities. The study of these models enable specific conditions that must be satisfied for the economic processes friendly coexist to the environment for long term, meaning to have a minimal impact in that the residues resulting from the economic activity of the organization to be as less harmful to the environment.

scholarly journals Long-Term Cryopreservation Does Not Affect Quality of Peripheral Blood Stem Cell Grafts: A Comparative Study of Native, Short-Term and Long-Term Cryopreserved Haematopoietic Stem Cells

2021 ◽  
Vol 30 ◽  
pp. 096368972110360
Author(s):  
Daniel Lysak ◽  
Michaela Brychtová ◽  
Martin Leba ◽  
Miroslava Čedíková ◽  
Daniel Georgiev ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Statistical Significance ◽  
Extended Period ◽  
High Dose ◽  
Atp Production ◽  
Cd34 Cells ◽  
Negative Effect

Cryopreserved haematopoietic progenitor cells are used to restore autologous haematopoiesis after high dose chemotherapy. Although the cells are routinely stored for a long period, concerns remain about the maximum storage time and the possible negative effect of storage on their potency. We evaluated the effect of cryopreservation on the quality of peripheral stem cell grafts stored for a short (3 months) and a long (10 years) period and we compared it to native products.The viability of CD34+ cells remained unaffected during storage, the apoptotic cells were represented up to 10% and did not differ between groups. The clonogenic activity measured by ATP production has decreased with the length of storage (ATP/cell 1.28 nM in native vs. 0.63 in long term stored products, P < 0.05). Only borderline changes without statistical significance were detected when examining mitochondrial and aldehyde dehydrogenase metabolic activity and intracellular pH, showing their good preservation during cell storage. Our experience demonstrates that cryostorage has no major negative effect on stem cell quality and potency, and therefore autologous stem cells can be stored safely for an extended period of at least 10 years. On the other hand, long term storage for 10 years and longer may lead to mild reduction of clonogenic capacity. When a sufficient dose of stem cells is infused, these changes will not have a clinical impact. However, in products stored beyond 10 years, especially when a low number of CD34+ cells is available, the quality of stem cell graft should be verified before infusion using the appropriate potency assays.

scholarly journals Long-term subjective memory after electroconvulsive therapy

BJPsych Open ◽  
2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Robert Sigström ◽  
Axel Nordenskjöld ◽  
Anders Juréus ◽  
Caitlin Clements ◽  
Erik Joas ◽  
...  
Keyword(s):  
Electroconvulsive Therapy ◽  
Memory Impairment ◽  
Rating Scale ◽  
Final Analysis ◽  
Negative Effects ◽  
Subjective Memory ◽  
Subjective Memory Impairment ◽  
Negative Effect ◽  
Negative Expectations

Background There have been reports of long-term subjective memory worsening after electroconvulsive therapy (ECT). Aims To study the prevalence and risk factors of long-term subjective memory worsening among patients receiving ECT in routine clinical practice. Method Patients (n = 535, of whom 277 were included in the final analysis) were recruited from eight Swedish hospitals. Participants' subjective memory impairment was assessed before ECT and a median of 73 days after ECT using the memory item from the Comprehensive Psychopathological Rating Scale. Participants also rated their pre-ECT expectations and post-ECT evaluations of the effect of ECT on memory on a 7-point scale. We used ordinal regression to identify variables associated with subjective memory worsening and negative evaluations of the effect of ECT on memory. Results Comparisons of pre- and post-ECT assessments showed that subjective memory worsened in 16.2% of participants, remained unchanged in 52.3% and improved in 31.4%. By contrast, when asked to evaluate the effect of ECT on memory after treatment 54.6% reported a negative effect. Subjective memory worsening was associated with negative expectations before ECT, younger age and shorter duration of follow-up. Conclusions Although subjective memory improved more often than it worsened when assessed before and after ECT, a majority of patients reported that ECT had negative effects on their memory when retrospectively asked how ECT had affected it. This might suggest that some patients attribute pre-existing subjective memory impairment to ECT. Clinicians should be aware that negative expectations are associated with subjective worsening of memory after ECT.

scholarly journals Can communication with social robots influence how children develop empathy? Best-evidence synthesis

AI & Society ◽  
2021 ◽  
Author(s):  
Ekaterina Pashevich
Keyword(s):  
Emotional Development ◽  
Evidence Synthesis ◽  
Social Robots ◽  
Human Robot Interaction ◽  
Emotional Engagement ◽  
Social And Emotional Development ◽  
Social And Emotional ◽  
Best Evidence Synthesis ◽  
Negative Effect

AbstractSocial robots are gradually entering children’s lives in a period when children learn about social relationships and exercise prosocial behaviors with parents, peers, and teachers. Designed for long-term emotional engagement and to take the roles of friends, teachers, and babysitters, such robots have the potential to influence how children develop empathy. This article presents a review of the literature (2010–2020) in the fields of human–robot interaction (HRI), psychology, neuropsychology, and roboethics, discussing the potential impact of communication with social robots on children’s social and emotional development. The critical analysis of evidence behind these discussions shows that, although robots theoretically have high chances of influencing the development of empathy in children, depending on their design, intensity, and context of use, there is no certainty about the kind of effect they might have. Most of the analyzed studies, which showed the ability of robots to improve empathy levels in children, were not longitudinal, while the studies observing and arguing for the negative effect of robots on children’s empathy were either purely theoretical or dependent on the specific design of the robot and the situation. Therefore, there is a need for studies investigating the effects on children’s social and emotional development of long-term regular and consistent communication with robots of various designs and in different situations.

scholarly journals Examining Eurozone Crisis and Unemployment Relationship Using Var Models

2013 ◽  
Vol 60 (2) ◽  
pp. 85-92
Author(s):  
Dimitrios Dapontas
Keyword(s):  
Government Spending ◽  
Eurozone Crisis ◽  
Var Models ◽  
Monthly Data ◽  
Distributed Lag ◽  
Distributed Lag Model ◽  
Negative Effect ◽  
Lag Model ◽  
The Relationship

Abstract This work examines the relationship between the Eurozone crisis and unemployment. We deploy distributed lag model using two binary (Crisis and crisis in another country) along with three (Government spending to GDP, Labor freedom, and urbanization) variables working as a long term factors applied on a six countries set (Cyprus, Greece, Ireland, Italy, Portugal and Spain respectively) spanning the period January1995-May 2012 in order to explain the unemployment change using VAR models on monthly data in contrast to longer frequency analyses. This innovative approach is determining the optimal lag length between unemployment and crises determining the time between turbulence and its effect to unemployment. The results show that optimal lag varies among two and eight months. Two variables seem to have negative effect on unemployment (Government spending to GDP, labor freedom) and one positive (urbanization).

Use of immunocorrectors in patients with chronic lymph leukemia

1986 ◽  
Vol 67 (2) ◽  
pp. 99-101
Author(s):  
V. Ya. Shustov ◽  
N. A. Afanasyeva ◽  
P. P. Kuznetsov ◽  
A. K. Myshkina
Keyword(s):  
Immune System ◽  
Outpatient Treatment ◽  
Infectious Complications ◽  
Chronic Lymphatic Leukemia ◽  
Cytostatic Drugs ◽  
Ability To Work ◽  
Lymphatic Leukemia ◽  
Long Time ◽  
Negative Effect

Chronic lymphatic leukemia is second only to acute leukemia in the frequency of infectious complications. In most cases, severe infectious complications are the cause of death in these patients. Modern chemotherapy makes it possible to preserve the ability to work and the life expectancy of patients for a long time. However, the negative effect of cytostatic drugs on the already altered immune system leads to an even greater suppression of immunity and an increase in the number of infectious complications. The search for new ways to combat infections has shown the advisability of long-term outpatient treatment with antibacterial drugs.

De relatie tussen herstel, werkdruk en slaap: een dagboekstudie

2010 ◽  
Vol 23 (4) ◽  
Author(s):  
Alicia L.T. Walkowiak ◽  
Ute R. Hülsheger ◽  
Fred R.H. Zijlstra
Keyword(s):  
Sleep Quality ◽  
Positive Influence ◽  
Mediating Effect ◽  
Mediation Effect ◽  
Diary Study ◽  
Work Pressure ◽  
Negative Effect ◽  
The Relationship ◽  
High Work

The relationship between recovery, work pressure and sleep quality: A diary study The relationship between recovery, work pressure and sleep quality: A diary study Alicia L.T. Walkowiak, Ute R.Hülsheger & Fred R.H. Zijlstra, Gedrag & Organisatie, volume 23, December 2010, nr. 4, pp. 316-332. Previous research showed that the experience of high work pressure can lead to fatigue and even to health complaints on the long term. This makes it very important, especially for people who experience high work pressure, to take sufficient time to recover after work. Sleep quality has a positive influence on recovery. The aim of this diary study was to investigate whether sleep quality has a mediating effect on the relationship between work pressure and recovery. Seventy-six people took part in the study and answered questions about work, recovery and sleep for 14 days. Results showed that work pressure indeed had a negative effect on recovery and sleep quality. Furthermore, we found a partial mediation effect: sleep quality mediated the relationship between work pressure and recovery. These results stress the importance of recovery and sleep quality, especially for people who experience high work pressure.

Sign in / Sign up

Export Citation Format

Share Document